Allow targets to self-select optimization level in official builds.

build/internal/release_impl_official.gypi

Index: build/internal/release_impl_official.gypi
diff --git a/build/internal/release_impl_official.gypi b/build/internal/release_impl_official.gypi
index d62e955250c8d8c8b54d13d4a16b5aeb87e768e3..8c133495aa8425c5be364085474d65af1fede623 100644
--- a/build/internal/release_impl_official.gypi
+++ b/build/internal/release_impl_official.gypi
@@ -1,23 +1,23 @@
+# Copyright (c) 2011 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.
 {
   'includes': ['release_defaults.gypi'],
   'defines': ['OFFICIAL_BUILD'],
   'msvs_settings': {
     'VCCLCompilerTool': {
-      'Optimization': '3',
       'InlineFunctionExpansion': '2',
       'EnableIntrinsicFunctions': 'true',
-      'FavorSizeOrSpeed': '2',
       'OmitFramePointers': 'true',
       'EnableFiberSafeOptimizations': 'true',
-      'WholeProgramOptimization': 'true',
     },
     'VCLibrarianTool': {
-      'AdditionalOptions': ['/ltcg', '/expectedoutputsize:120000000'],
+      'AdditionalOptions': [
+        '/ltcg',
+        '/expectedoutputsize:120000000'
+      ],
     },
     'VCLinkerTool': {
-      # Get more debug spew from the linker while we're sorting out
-      # build problems and performance.
-      # TODO(siggi): Remove these flags after we're out of the woods.
       'AdditionalOptions': [
         '/time',
         # This may reduce memory fragmentation during linking.