Re-enable warning 4701 for GN build and some cleanup

Clean up three 4701 warnings (use potientially uninitialized variable)
which are the only ones left;
Re-enable warning 4701 for GN build;
Remove an unused data structure;

BUG=pdfium:29

Review URL: https://codereview.chromium.org/1885093002

5 files changed, 6 insertions, 35 deletions

diff --git a/BUILD.gn b/BUILD.gn
index 74903bf682..bb0b5cb3c6 100644
--- a/BUILD.gn
+++ b/BUILD.gn
@@ -44,7 +44,6 @@ config("pdfium_config") {
   if (is_win) {
     cflags += [
       "/wd4267",
-      "/wd4701",
     ]
   }
 
diff --git a/core/fpdfapi/fpdf_edit/fpdf_edit_doc.cpp b/core/fpdfapi/fpdf_edit/fpdf_edit_doc.cpp
index 379e75938e..c3d4ca621a 100644
--- a/core/fpdfapi/fpdf_edit/fpdf_edit_doc.cpp
+++ b/core/fpdfapi/fpdf_edit/fpdf_edit_doc.cpp
@@ -354,7 +354,7 @@ CPDF_Font* CPDF_Document::AddWindowsFont(LOGFONTA* pLogFont,
     pFontDict = new CPDF_Dictionary;
     CFX_ByteString cmap;
     CFX_ByteString ordering;
-    int supplement;
+    int supplement = 0;
     CPDF_Array* pWidthArray = new CPDF_Array;
     switch (pLogFont->lfCharSet) {
       case CHINESEBIG5_CHARSET:
diff --git a/core/fpdfapi/fpdf_render/fpdf_render_pattern.cpp b/core/fpdfapi/fpdf_render/fpdf_render_pattern.cpp
index 48f9f5d98a..6ac380e43a 100644
--- a/core/fpdfapi/fpdf_render/fpdf_render_pattern.cpp
+++ b/core/fpdfapi/fpdf_render/fpdf_render_pattern.cpp
@@ -653,7 +653,10 @@ struct CPDF_PatchDrawer {
     FX_BOOL bSmall = C1.Distance() < 2 && C2.Distance() < 2 &&
                      D1.Distance() < 2 && D2.Distance() < 2;
     Coon_Color div_colors[4];
-    int d_bottom, d_left, d_top, d_right;
+    int d_bottom = 0;
+    int d_left = 0;
+    int d_top = 0;
+    int d_right = 0;
     div_colors[0].BiInterpol(patch_colors, left, bottom, x_scale, y_scale);
     if (!bSmall) {
       div_colors[1].BiInterpol(patch_colors, left, bottom + 1, x_scale,
diff --git a/core/fxcodec/jbig2/JBig2_Context.cpp b/core/fxcodec/jbig2/JBig2_Context.cpp
index 1ff78e121f..5a0b2c0d73 100644
--- a/core/fxcodec/jbig2/JBig2_Context.cpp
+++ b/core/fxcodec/jbig2/JBig2_Context.cpp
@@ -1285,7 +1285,7 @@ JBig2HuffmanCode* CJBig2_Context::decodeSymbolIDHuffmanTable(
 
   std::unique_ptr<JBig2HuffmanCode, FxFreeDeleter> SBSYMCODES(
       FX_Alloc(JBig2HuffmanCode, SBNUMSYMS));
-  int32_t run;
+  int32_t run = 0;
   int32_t i = 0;
   while (i < (int)SBNUMSYMS) {
     size_t j;
diff --git a/xfa/fgas/localization/fgas_datetime.h b/xfa/fgas/localization/fgas_datetime.h
index df2989fc58..7c8f111bfc 100644
--- a/xfa/fgas/localization/fgas_datetime.h
+++ b/xfa/fgas/localization/fgas_datetime.h
@@ -205,37 +205,6 @@ struct FX_DATETIME {
   } Time;
 };
 
-struct FX_DATETIMEZONE {
-  union {
-    struct {
-      union {
-        struct {
-          int32_t year;
-          uint8_t month;
-          uint8_t day;
-        };
-        FX_DATE date;
-      };
-      union {
-        struct {
-          uint8_t hour;
-          uint8_t minute;
-          uint8_t second;
-          uint16_t millisecond;
-        };
-        FX_TIME time;
-      };
-    };
-    FX_DATETIME dt;
-  };
-  union {
-    struct {
-      int8_t tzHour;
-      uint8_t tzMinute;
-    };
-    FX_TIMEZONE tz;
-  };
-};
 #if _FX_OS_ != _FX_ANDROID_
 #pragma pack(pop)
 #endif