Fix GN unit tests on Windows, GN x64 build.

tools/gn/source_dir_unittest.cc

 // Copyright (c) 2013 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "testing/gtest/include/gtest/gtest.h"
 #include "tools/gn/source_dir.h"
 #include "tools/gn/source_file.h"
 
-// Fails on windows. http://crbug.com/458939
-#if defined(OS_WIN)
-#define MAYBE_ResolveRelativeFile DISABLED_ResolveRelativeFile
-#else
-#define MAYBE_ResolveRelativeFile ResolveRelativeFile
-#endif
-TEST(SourceDir, MAYBE_ResolveRelativeFile) {
+TEST(SourceDir, ResolveRelativeFile) {
   SourceDir base("//base/");
 #if defined(OS_WIN)
   base::StringPiece source_root("C:/source/root");
 #else
   base::StringPiece source_root("/source/root");
 #endif
 
   // Empty input is an error.
   EXPECT_TRUE(base.ResolveRelativeFile("", source_root) == SourceFile());
 
@@ skipping 14 matching lines @@
               SourceFile("//base/foo"));
   EXPECT_TRUE(base.ResolveRelativeFile("./foo", source_root) ==
               SourceFile("//base/foo"));
   EXPECT_TRUE(base.ResolveRelativeFile("../foo", source_root) ==
               SourceFile("//foo"));
 
   // If the given relative path points outside the source root, we
   // expect an absolute path.
 #if defined(OS_WIN)
   EXPECT_TRUE(base.ResolveRelativeFile("../../foo", source_root) ==
-              SourceFile("C:/source/foo"));
+              SourceFile("/C:/source/foo"));
 #else
   EXPECT_TRUE(base.ResolveRelativeFile("../../foo", source_root) ==
               SourceFile("/source/foo"));
 #endif
 
 #if defined(OS_WIN)
   // Note that we don't canonicalize the backslashes to forward slashes.
   // This could potentially be changed in the future which would mean we should
   // just change the expected result.
   EXPECT_TRUE(base.ResolveRelativeFile("C:\\foo\\bar.txt", source_root) ==
               SourceFile("/C:/foo/bar.txt"));
 #endif
 }
 
-// Fails on windows. http://crbug.com/458939
-#if defined(OS_WIN)
-#define MAYBE_ResolveRelativeDir DISABLED_ResolveRelativeDir
-#else
-#define MAYBE_ResolveRelativeDir ResolveRelativeDir
-#endif
-TEST(SourceDir, MAYBE_ResolveRelativeDir) {
+TEST(SourceDir, ResolveRelativeDir) {
   SourceDir base("//base/");
 #if defined(OS_WIN)
   base::StringPiece source_root("C:/source/root");
 #else
   base::StringPiece source_root("/source/root");
 #endif
 
   // Empty input is an error.
   EXPECT_TRUE(base.ResolveRelativeDir("", source_root) == SourceDir());
 
   // Absolute paths should be passed unchanged.
   EXPECT_TRUE(base.ResolveRelativeDir("//foo", source_root) ==
               SourceDir("//foo/"));
   EXPECT_TRUE(base.ResolveRelativeDir("/foo", source_root) ==
               SourceDir("/foo/"));
 
   // Basic relative stuff.
   EXPECT_TRUE(base.ResolveRelativeDir("foo", source_root) ==
               SourceDir("//base/foo/"));
   EXPECT_TRUE(base.ResolveRelativeDir("./foo", source_root) ==
               SourceDir("//base/foo/"));
   EXPECT_TRUE(base.ResolveRelativeDir("../foo", source_root) ==
               SourceDir("//foo/"));
 
   // If the given relative path points outside the source root, we
   // expect an absolute path.
 #if defined(OS_WIN)
   EXPECT_TRUE(base.ResolveRelativeDir("../../foo", source_root) ==
-              SourceDir("C:/source/foo/"));
+              SourceDir("/C:/source/foo/"));
 #else
   EXPECT_TRUE(base.ResolveRelativeDir("../../foo", source_root) ==
               SourceDir("/source/foo/"));
 #endif
 
 #if defined(OS_WIN)
-  // Note that we don't canonicalize the existing backslashes to forward
-  // slashes. This could potentially be changed in the future which would mean
-  // we should just change the expected result.
+  // Canonicalize the existing backslashes to forward slashes and add a
+  // leading slash if necessary.
+  EXPECT_TRUE(base.ResolveRelativeDir("\\C:\\foo") == SourceDir("/C:/foo/"));
   EXPECT_TRUE(base.ResolveRelativeDir("C:\\foo") == SourceDir("/C:/foo/"));
 #endif
 }