Add PGO targets to Chrome.

chrome/chrome_pgo.gypi

Index: chrome/chrome_pgo.gypi
diff --git a/chrome/chrome_pgo.gypi b/chrome/chrome_pgo.gypi
new file mode 100644
index 0000000000000000000000000000000000000000..0fb90b416c20153cc3044a051f2a24f9618676a1
--- /dev/null
+++ b/chrome/chrome_pgo.gypi
@@ -0,0 +1,73 @@
+# 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"', {
+      'targets': [
+        # In the PGO (Profile-Guided Optimization) build flow, we need to
+        # build the target binary multiple times. To implement this flow with
+        # gyp, here we define multiple targets, each of which represents one
+        # build particular build/profile stage.
+        {
+          'target_name': 'chrome_pgo_main',
+          'type': 'none',

[yukawa, 2014/03/07 05:25:22]

Does this really work?  The 'type' is 'none' here. I'm worried about whether
linker action is kicked here or not. I guess it depends on how the target
generator is implemented in GYP.

+          'dependencies': [ 'chrome_main_dll', ],
+          'msvs_settings': {
+            'VCCLCompilerTool': {
+              'WholeProgramOptimization': 'true',  # /GL
+            },
+            'VCLibrarianTool': {
+              'LinkTimeCodeGeneration': 'true',
+            },
+          },
+          'link_settings': {
+            'msvs_settings': {
+              'VCLinkerTool': {
+                # Tell ninja generator not to pass /ManifestFile:<filename>

[yukawa, 2014/03/07 05:25:22]

You might be able to drop this hack.  I added this for the VS 2008's linker
because one of gyp build bots was still using it.  I guess having some consensus
about which version of Visual C++ will be supported in Chromium regarding PGO
makes things easy.

+                # option to the linker, because it causes LNK1268 error in PGO
+                # build.
+                'GenerateManifest': 'false',
+              },
+            },
+          },
+        }, {
+          'target_name': 'chrome_pgo_instrument',
+          'type': 'none',
+          'msvs_settings': {
+            'VCLinkerTool': {
+              'LinkTimeCodeGeneration': '2',
+            },
+          },
+          'dependencies': [
+            'chrome_pgo_main',
+          ],
+        }, {
+          'target_name': 'chrome_pgo_optimize',
+          'type': 'none',
+          'msvs_settings': {
+            'VCLinkerTool': {
+              'LinkTimeCodeGeneration': '3',
+            },
+          },
+          'dependencies': [
+            # TODO(sebmarchand): Add a target that run some profile test cases.
+            'chrome_pgo_instrument',
+            'chrome_pgo_main',
+          ],
+        }, {
+          'target_name': 'chrome_pgo_update',
+          'type': 'none',
+          'msvs_settings': {
+            'VCLinkerTool': {
+              'LinkTimeCodeGeneration': '4',
+            },
+          },
+          'dependencies': [
+            'chrome_pgo_main',
+          ],
+        },
+      ],
+    }],
+  ],
+}