Reland "Introduce FX_Number class as a replacement for FX_atonum()."

This reverts commit 29e180342e18873babf1c74f7c5c056f90a191b0.

Reason for revert: probably harmless

Original change's description:
> Revert "Introduce FX_Number class as a replacement for FX_atonum()."
>
> This reverts commit a5d7ad3aa8feb08a14b5cca173d673054c1ade23.
>
> Reason for revert: Speculative revert to get back before flake.
>
> Original change's description:
> > Introduce FX_Number class as a replacement for FX_atonum().
> >
> > The issue with FX_atonum() is that it doesn't return any information
> > about whether it range-checked its integer values as a signed or
> > unsigned type, even though it knows this as part of its processing.
> >
> > Rather than adding another out parameter to that function, create
> > a class to hold all this information together.
> >
> > This is the first place things went astray while diagnosing
> > bug 882959, in that a large positive value was cast to float as a
> > negative value. Unfortunately, this doesn't affect the related bug,
> > but is a step in the right direction.
> >
> > Change-Id: I0977ec8fccf85e2632a962507bdd30a1cbe6d33c
> > Reviewed-on: https://pdfium-review.googlesource.com/42353
> > Reviewed-by: Lei Zhang <thestig@chromium.org>
> > Commit-Queue: Tom Sepez <tsepez@chromium.org>
>
> TBR=thestig@chromium.org,tsepez@chromium.org
>
> Change-Id: Ia56270c3daa80408fc2b23eb4384a77f03f45b82
> Reviewed-on: https://pdfium-review.googlesource.com/42392
> Reviewed-by: Tom Sepez <tsepez@chromium.org>
> Commit-Queue: Tom Sepez <tsepez@chromium.org>

TBR=thestig@chromium.org,tsepez@chromium.org

Change-Id: I83c37aa3040a8890f2117753f19ab1d452d411e7
Reviewed-on: https://pdfium-review.googlesource.com/42410
Commit-Queue: Tom Sepez <tsepez@chromium.org>
Reviewed-by: Tom Sepez <tsepez@chromium.org>

1 files changed, 0 insertions, 47 deletions

diff --git a/core/fxcrt/fx_string_unittest.cpp b/core/fxcrt/fx_string_unittest.cpp
index 60e7f07523..3059de3e5c 100644
--- a/core/fxcrt/fx_string_unittest.cpp
+++ b/core/fxcrt/fx_string_unittest.cpp
@@ -2,56 +2,9 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-#include <limits>
-
 #include "core/fxcrt/fx_string.h"
 #include "testing/gtest/include/gtest/gtest.h"
 
-TEST(fxstring, FX_atonum) {
-  int i;
-  EXPECT_TRUE(FX_atonum("10", &i));
-  EXPECT_EQ(10, i);
-
-  EXPECT_TRUE(FX_atonum("-10", &i));
-  EXPECT_EQ(-10, i);
-
-  EXPECT_TRUE(FX_atonum("+10", &i));
-  EXPECT_EQ(10, i);
-
-  EXPECT_TRUE(FX_atonum("-2147483648", &i));
-  EXPECT_EQ(std::numeric_limits<int>::min(), i);
-
-  EXPECT_TRUE(FX_atonum("2147483647", &i));
-  EXPECT_EQ(2147483647, i);
-
-  // Value overflows.
-  EXPECT_TRUE(FX_atonum("-2147483649", &i));
-  EXPECT_EQ(0, i);
-
-  // Value overflows.
-  EXPECT_TRUE(FX_atonum("+2147483648", &i));
-  EXPECT_EQ(0, i);
-
-  // Value overflows.
-  EXPECT_TRUE(FX_atonum("4223423494965252", &i));
-  EXPECT_EQ(0, i);
-
-  // No explicit sign will allow the number to go negative. This is for things
-  // like the encryption Permissions flag (Table 3.20 PDF 1.7 spec)
-  EXPECT_TRUE(FX_atonum("4294965252", &i));
-  EXPECT_EQ(-2044, i);
-
-  EXPECT_TRUE(FX_atonum("-4294965252", &i));
-  EXPECT_EQ(0, i);
-
-  EXPECT_TRUE(FX_atonum("+4294965252", &i));
-  EXPECT_EQ(0, i);
-
-  float f;
-  EXPECT_FALSE(FX_atonum("3.24", &f));
-  EXPECT_FLOAT_EQ(3.24f, f);
-}
-
 TEST(fxstring, FX_UTF8Encode) {
   EXPECT_EQ("", FX_UTF8Encode(WideStringView()));
   EXPECT_EQ(