Add PGO targets to Chrome.

chrome/chrome_pgo.gypi

+# Copyright (c) 2014 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.
+{
+  'conditions': [
+    ['OS=="win"', {
+      # Instrumentation step.
+      'variables': {
+        # Corresponds to the /LTCG:PGINSTRUMENT option.
+        'ltcg_value': '2',
+        'chrome_dll_target_name': 'chrome_dll_pgi',
+        'chrome_main_dll_target_name': 'chrome_main_dll_pgi',
+        'chrome_main_dll_product_name': 'chrome_pgi',
+        'chrome_child_dll_target_name': 'chrome_child_dll_pgi',
+        'chrome_child_dll_product_name': 'chrome_child_pgi',
+      },
+      'includes': [
+        'chrome_dll.gypi',
+      ],
+      'targets': [
+        # Profiling step.
+        {
+          'target_name': 'chrome_pgo_profile',
+          'type': 'none',
+          # TODO(sebmarchand): Rename the dll produced in the
+          #     'chrome_pgo_instrument' step and profile Chrome.
+          'dependencies': [
+            'chrome_main_dll_pgi',
+            'chrome_child_dll_pgi',
+          ],
+        },
+      ],
+    }],
+    ['chrome_pgo==1', {
+      # Optimization step.
+      'variables': {
+        # Corresponds to the /LTCG:PGOPTIMIZE option.
+        'ltcg_value': '3',
+        'chrome_dll_target_name': 'chrome_dll',
+        'chrome_main_dll_target_name': 'chrome_main_dll',
+        'chrome_main_dll_product_name': 'chrome',
+        'chrome_child_dll_target_name': 'chrome_child_dll',
+        'chrome_child_dll_product_name': 'chrome_child',
+      },
+      'includes': [
+        'chrome_dll.gypi',
+      ],
+    }],
+  ],
+}