Revert "Remove ContrastAdjust()."

This reverts commit 53d443f042b590ae2d920def16bc9daf66f8427d.

Reason for revert: Breaks PDFToPWGRasterBrowserTest

Original change's description:
> Remove ContrastAdjust().
> 
> This post-processing increased the contrast of scaled-down features -
> mainly lines and fonts, relative to the background. The effect does not
> improved readability and in some cases makes the scaled-down version
> look like a different document at a glance. Text that is normal
> weight appears bold when scaled down in these cases.
> 
> Change-Id: I2544d45e2bcec25d6742d2a60c1316d8df08cce1
> Reviewed-on: https://pdfium-review.googlesource.com/15471
> Commit-Queue: Henrique Nakashima <hnakashima@chromium.org>
> Reviewed-by: dsinclair <dsinclair@chromium.org>

TBR=bungeman@chromium.org,dsinclair@chromium.org,hnakashima@chromium.org

# Not skipping CQ checks because original CL landed > 1 day ago.

Change-Id: I7f61650bc6d917b3c6640da60f3f740ef4498de0
Reviewed-on: https://pdfium-review.googlesource.com/16970
Commit-Queue: Henrique Nakashima <hnakashima@chromium.org>
Reviewed-by: Henrique Nakashima <hnakashima@chromium.org>

3 files changed, 41 insertions, 41 deletions

diff --git a/fpdfsdk/fpdfannot_embeddertest.cpp b/fpdfsdk/fpdfannot_embeddertest.cpp
index a569c1037b..fbcd9f2972 100644
--- a/fpdfsdk/fpdfannot_embeddertest.cpp
+++ b/fpdfsdk/fpdfannot_embeddertest.cpp
@@ -283,7 +283,7 @@ TEST_F(FPDFAnnotEmbeddertest, AddAndSaveUnderlineAnnotation) {
   FPDF_ClosePage(page);
 
   // Open the saved document.
-  const char md5[] = "dba153419f67b7c0c0e3d22d3e8910d5";
+  const char md5[] = "184b67b322edaee27994b3232544b8b3";
 
   OpenSavedDocument();
   LoadSavedPage();
@@ -316,13 +316,13 @@ TEST_F(FPDFAnnotEmbeddertest, ModifyRectQuadpointsWithAP) {
   const char md5_modified_highlight[] = "aec26075011349dec9bace891856b5f2";
   const char md5_modified_square[] = "057f57a32be95975775e5ec513fdcb56";
 #elif _FX_PLATFORM_ == _FX_PLATFORM_WINDOWS_
-  const char md5_original[] = "0e27376094f11490f74c65f3dc3a42c5";
-  const char md5_modified_highlight[] = "66f3caef3a7d488a4fa1ad37fc06310e";
-  const char md5_modified_square[] = "a456dad0bc6801ee2d6408a4394af563";
+  const char md5_original[] = "ade6762a70e85605546ce067e7d2148f";
+  const char md5_modified_highlight[] = "fb8440ed1a070b53ed5598ce7451cfad";
+  const char md5_modified_square[] = "7925f6726b343393f258e8b4e93dd65d";
 #else
-  const char md5_original[] = "0e27376094f11490f74c65f3dc3a42c5";
-  const char md5_modified_highlight[] = "66f3caef3a7d488a4fa1ad37fc06310e";
-  const char md5_modified_square[] = "a456dad0bc6801ee2d6408a4394af563";
+  const char md5_original[] = "ade6762a70e85605546ce067e7d2148f";
+  const char md5_modified_highlight[] = "fb8440ed1a070b53ed5598ce7451cfad";
+  const char md5_modified_square[] = "7925f6726b343393f258e8b4e93dd65d";
 #endif
 
   // Open a file with four annotations and load its first page.
@@ -492,15 +492,15 @@ TEST_F(FPDFAnnotEmbeddertest, AddAndModifyPath) {
   const char md5_two_paths[] = "e8994452fc4385337bae5522354e10ff";
   const char md5_new_annot[] = "ee5372b31fede117fc83b9384598aa25";
 #elif _FX_PLATFORM_ == _FX_PLATFORM_WINDOWS_
-  const char md5_original[] = "964f89bbe8911e540a465cf1a64b7f7e";
-  const char md5_modified_path[] = "3f77b88ce6048e08e636c9a03921b2e5";
-  const char md5_two_paths[] = "bffbf5ecd15862b9fe553c795400ff8e";
-  const char md5_new_annot[] = "e020534c7eeea76be537c70d6e359a40";
+  const char md5_original[] = "4f64add0190ede63f7bb9eb1e2e83edb";
+  const char md5_modified_path[] = "681f0d0738dded0722e146f6c219bfac";
+  const char md5_two_paths[] = "67c7e90fc3b64e20f6b69a1744f7f4f0";
+  const char md5_new_annot[] = "262187984451bae2fe826067d68623ff";
 #else
-  const char md5_original[] = "964f89bbe8911e540a465cf1a64b7f7e";
-  const char md5_modified_path[] = "3f77b88ce6048e08e636c9a03921b2e5";
-  const char md5_two_paths[] = "bffbf5ecd15862b9fe553c795400ff8e";
-  const char md5_new_annot[] = "e020534c7eeea76be537c70d6e359a40";
+  const char md5_original[] = "4f64add0190ede63f7bb9eb1e2e83edb";
+  const char md5_modified_path[] = "681f0d0738dded0722e146f6c219bfac";
+  const char md5_two_paths[] = "67c7e90fc3b64e20f6b69a1744f7f4f0";
+  const char md5_new_annot[] = "262187984451bae2fe826067d68623ff";
 #endif
 
   // Open a file with two annotations and load its first page.
@@ -673,13 +673,13 @@ TEST_F(FPDFAnnotEmbeddertest, AddAndModifyImage) {
   const char md5_new_image[] = "ff012f5697436dfcaec25b32d1333596";
   const char md5_modified_image[] = "86cf8cb2755a7a2046a543e66d9c1e61";
 #elif _FX_PLATFORM_ == _FX_PLATFORM_WINDOWS_
-  const char md5_original[] = "964f89bbe8911e540a465cf1a64b7f7e";
-  const char md5_new_image[] = "9ea8732dc9d579f68853f16892856208";
-  const char md5_modified_image[] = "74239d2a8c55c9de1dbb9cd8781895aa";
+  const char md5_original[] = "4f64add0190ede63f7bb9eb1e2e83edb";
+  const char md5_new_image[] = "6fb176c20996cc554d0210d8c8b6138f";
+  const char md5_modified_image[] = "546959714dfb0dcd7e7b00259e8d178c";
 #else
-  const char md5_original[] = "964f89bbe8911e540a465cf1a64b7f7e";
-  const char md5_new_image[] = "9ea8732dc9d579f68853f16892856208";
-  const char md5_modified_image[] = "74239d2a8c55c9de1dbb9cd8781895aa";
+  const char md5_original[] = "4f64add0190ede63f7bb9eb1e2e83edb";
+  const char md5_new_image[] = "6fb176c20996cc554d0210d8c8b6138f";
+  const char md5_modified_image[] = "546959714dfb0dcd7e7b00259e8d178c";
 #endif
 
   // Open a file with two annotations and load its first page.
@@ -750,13 +750,13 @@ TEST_F(FPDFAnnotEmbeddertest, AddAndModifyText) {
   const char md5_new_text[] = "e5680ed048c2cfd9a1d27212cdf41286";
   const char md5_modified_text[] = "79f5cfb0b07caaf936f65f6a7a57ce77";
 #elif _FX_PLATFORM_ == _FX_PLATFORM_WINDOWS_
-  const char md5_original[] = "964f89bbe8911e540a465cf1a64b7f7e";
-  const char md5_new_text[] = "00b14fa2dc1c90d1b0d034e1608efef5";
-  const char md5_modified_text[] = "076c8f24a09ddc0e49f7e758edead6f0";
+  const char md5_original[] = "4f64add0190ede63f7bb9eb1e2e83edb";
+  const char md5_new_text[] = "998abae4962f8f41e094e7612d8339fc";
+  const char md5_modified_text[] = "e89b82ca4589b8f0b45fff42ca3a96a4";
 #else
-  const char md5_original[] = "964f89bbe8911e540a465cf1a64b7f7e";
-  const char md5_new_text[] = "00b14fa2dc1c90d1b0d034e1608efef5";
-  const char md5_modified_text[] = "076c8f24a09ddc0e49f7e758edead6f0";
+  const char md5_original[] = "4f64add0190ede63f7bb9eb1e2e83edb";
+  const char md5_new_text[] = "998abae4962f8f41e094e7612d8339fc";
+  const char md5_modified_text[] = "e89b82ca4589b8f0b45fff42ca3a96a4";
 #endif
 
   // Open a file with two annotations and load its first page.
@@ -880,9 +880,9 @@ TEST_F(FPDFAnnotEmbeddertest, GetSetStringValue) {
 #if _FX_PLATFORM_ == _FX_PLATFORM_APPLE_
   const char md5[] = "4d64e61c9c0f8c60ab3cc3234bb73b1c";
 #elif _FX_PLATFORM_ == _FX_PLATFORM_WINDOWS_
-  const char md5[] = "c96ee1f316d7f5a1b154de9f9d467f01";
+  const char md5[] = "0e3710ea6476f5bcba2cd39eb42d54e2";
 #else
-  const char md5[] = "c96ee1f316d7f5a1b154de9f9d467f01";
+  const char md5[] = "0e3710ea6476f5bcba2cd39eb42d54e2";
 #endif
   OpenSavedDocument();
   LoadSavedPage();
diff --git a/fpdfsdk/fpdfedit_embeddertest.cpp b/fpdfsdk/fpdfedit_embeddertest.cpp
index f1f02ffa6d..60db27ad0c 100644
--- a/fpdfsdk/fpdfedit_embeddertest.cpp
+++ b/fpdfsdk/fpdfedit_embeddertest.cpp
@@ -422,7 +422,7 @@ TEST_F(FPDFEditEmbeddertest, PathOnTopOfText) {
 #if _FX_PLATFORM_ == _FX_PLATFORM_APPLE_
   const char md5[] = "f9e6fa74230f234286bfcada9f7606d8";
 #else
-  const char md5[] = "aa71b09b93b55f467f1290e5111babee";
+  const char md5[] = "bc6e6eb50dda4695ba0fb4d04ed82ada";
 #endif
   CompareBitmap(bitmap, 200, 200, md5);
   FPDFBitmap_Destroy(bitmap);
@@ -551,7 +551,7 @@ TEST_F(FPDFEditEmbeddertest, AddStandardFontText) {
 #if _FX_PLATFORM_ == _FX_PLATFORM_APPLE_
   const char md5[] = "a4dddc1a3930fa694bbff9789dab4161";
 #else
-  const char md5[] = "eacaa24573b8ce997b3882595f096f00";
+  const char md5[] = "7a35771853a1cbba38f6775807878625";
 #endif
   CompareBitmap(page_bitmap, 612, 792, md5);
   FPDFBitmap_Destroy(page_bitmap);
@@ -569,9 +569,9 @@ TEST_F(FPDFEditEmbeddertest, AddStandardFontText) {
 #if _FX_PLATFORM_ == _FX_PLATFORM_APPLE_
   const char md5_2[] = "a5c4ace4c6f27644094813fe1441a21c";
 #elif _FX_PLATFORM_ == _FX_PLATFORM_WINDOWS_
-  const char md5_2[] = "2587eac9a787e97a37636d54d11bd28d";
+  const char md5_2[] = "b231b329a4b566fb9b42bfc15fe59bb7";
 #else
-  const char md5_2[] = "76fcc7d08aa15445efd2e2ceb7c6cc3b";
+  const char md5_2[] = "f85fae151851436072b7b3c6703e506a";
 #endif
   CompareBitmap(page_bitmap, 612, 792, md5_2);
   FPDFBitmap_Destroy(page_bitmap);
@@ -589,9 +589,9 @@ TEST_F(FPDFEditEmbeddertest, AddStandardFontText) {
 #if _FX_PLATFORM_ == _FX_PLATFORM_APPLE_
   const char md5_3[] = "40b3ef04f915ff4c4208948001763544";
 #elif _FX_PLATFORM_ == _FX_PLATFORM_WINDOWS_
-  const char md5_3[] = "7cb61ec112cf400b489360d443ffc9d2";
+  const char md5_3[] = "ba874b3b137f984510c4e287ed4ba7ae";
 #else
-  const char md5_3[] = "b8a21668f1dab625af7c072e07fcefc4";
+  const char md5_3[] = "c5aed6a8ef05558c8c47d58c87cbcb46";
 #endif
   CompareBitmap(page_bitmap, 612, 792, md5_3);
   FPDFBitmap_Destroy(page_bitmap);
@@ -892,7 +892,7 @@ TEST_F(FPDFEditEmbeddertest, AddTrueTypeFontText) {
 #if _FX_PLATFORM_ == _FX_PLATFORM_APPLE_
     const char md5[] = "17d2b6cd574cf66170b09c8927529a94";
 #else
-    const char md5[] = "70592859010ffbf532a2237b8118bcc4";
+    const char md5[] = "1722c6a9deed953d730de9cd13dcbd55";
 #endif  // _FX_PLATFORM_ == _FX_PLATFORM_APPLE_
     CompareBitmap(page_bitmap, 612, 792, md5);
     FPDFBitmap_Destroy(page_bitmap);
@@ -910,7 +910,7 @@ TEST_F(FPDFEditEmbeddertest, AddTrueTypeFontText) {
 #if _FX_PLATFORM_ == _FX_PLATFORM_APPLE_
   const char md5_2[] = "8eded4193ff1f0f77b8b600a825e97ea";
 #else
-  const char md5_2[] = "c1d10cce1761c4a998a16b2562030568";
+  const char md5_2[] = "9d7885072058f6c3e68ecaf32e917f30";
 #endif  // _FX_PLATFORM_ == _FX_PLATFORM_APPLE_
   CompareBitmap(page_bitmap2, 612, 792, md5_2);
   FPDFBitmap_Destroy(page_bitmap2);
@@ -985,7 +985,7 @@ TEST_F(FPDFEditEmbeddertest, AddCIDFontText) {
 
   // Check that the text renders properly.
   FPDF_BITMAP page_bitmap = RenderPage(page);
-  const char md5[] = "c68cd79aa72bf83a7b25271370d46b21";
+  const char md5[] = "2bc6c1aaa2252e73246a75775ccf38c2";
   CompareBitmap(page_bitmap, 612, 792, md5);
   FPDFBitmap_Destroy(page_bitmap);
 
diff --git a/fpdfsdk/fpdfformfill_embeddertest.cpp b/fpdfsdk/fpdfformfill_embeddertest.cpp
index ae1c02ede1..4a3fc03d24 100644
--- a/fpdfsdk/fpdfformfill_embeddertest.cpp
+++ b/fpdfsdk/fpdfformfill_embeddertest.cpp
@@ -524,9 +524,9 @@ TEST_F(FPDFFormFillEmbeddertest, FormText) {
   const char md5_2[] = "35b1a4b679eafc749a0b6fda750c0e8d";
   const char md5_3[] = "65c64a7c355388f719a752aa1e23f6fe";
 #else
-  const char md5_1[] = "b890950d4b9bc163b1a96797f3004b53";
-  const char md5_2[] = "11487d5597599a26e8912b9c1d9422cb";
-  const char md5_3[] = "bffe0ecea9a533f217047ee41d6be466";
+  const char md5_1[] = "a5e3ac74c2ee123ec6710e2f0ef8424a";
+  const char md5_2[] = "4526b09382e144d5506ad92149399de6";
+  const char md5_3[] = "80356067d860088864cf50ff85d8459e";
 #endif
   {
     EXPECT_TRUE(OpenDocument("text_form.pdf"));