GTTF: Generate enough debug info for fastbuild=1 to get meaningful stack traces.

build/common.gypi

 # Copyright (c) 2012 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.
 
 # IMPORTANT:
 # Please don't directly include this file if you are building via gyp_chromium,
 # since gyp_chromium is automatically forcing its inclusion.
 {
   # Variables expected to be overriden on the GYP command line (-D) or by
   # ~/.gyp/include.gypi.
@@ skipping 1737 matching lines @@
                   'release_extra_cflags': '-g0',
                 },
               }],
             ],
           }, { # else clang!=1
             'conditions': [
               # For Windows and Mac, we don't genererate debug information.
               ['OS=="win"', {
                 'msvs_settings': {
                   'VCLinkerTool': {
-                    'GenerateDebugInformation': 'false',
+                    # This tells the linker to generate .pdbs, so that
+                    # we can get meaningful stack traces.
+                    'GenerateDebugInformation': 'true',
                   },
                   'VCCLCompilerTool': {
+                    # No debug info to be generated by compiler.
                     'DebugInformationFormat': '0',
                   },
                 },
               }],
               ['OS=="mac"', {
                 'xcode_settings': {
                   'GCC_GENERATE_DEBUGGING_SYMBOLS': 'NO',
                 },
               }],
               ['OS=="linux"', {
@@ skipping 2211 matching lines @@
     # settings in target dicts.  SYMROOT is a special case, because many other
     # Xcode variables depend on it, including variables such as
     # PROJECT_DERIVED_FILE_DIR.  When a source group corresponding to something
     # like PROJECT_DERIVED_FILE_DIR is added to a project, in order for the
     # files to appear (when present) in the UI as actual files and not red
     # red "missing file" proxies, the correct path to PROJECT_DERIVED_FILE_DIR,
     # and therefore SYMROOT, needs to be set at the project level.
     'SYMROOT': '<(DEPTH)/xcodebuild',
   },
 }