Force inclusion of build/common.gypi for all chromium gyp files.

Why: Simpler build code. If everybody includes it, it should be included automatically.
Why now: The webkit chromium builds need it be specified, since can't default to build/common.gypi.

What was done:
1. build/common.gypi's contents were moved to a new file build/gyp_chromium.gypi
2. tools/gyp/gyp_chromium was moved to build/gyp_chromium and made to automatically include build/gyp_chromium.gypi.
3. lots of gyp files were fixed to not refer to build/common.gypi any more.
4. o3d which also builds independently of chrome, was fixed to have a gyp_o3d that includes gyp_chromium.gypi too.
5. build/common.gypi was left empty, because there are some external projects that still refer to it.

Things that are left to do after this patch is in:
1. The following external files (in other repositories) need to stop include common.gypi
  ./third_party/hunspell/hunspell.gyp
  ./third_party/icu/icu.gyp
  ./v8/tools/gyp/v8.gyp
2. Once nobody refers to common.gypi anymore, delete common.gypi
   -or-
   Delete gyp_chromium.gypi and move its content back to common.gypi

Tested on mac, win and linux. On win, got a few unit tests errors on chrome bookmarks, which should not be related. I'm running again with clobber to verify.

Review URL: http://codereview.chromium.org/206006

git-svn-id: http://src.chromium.org/svn/trunk/src/build@26302 4ff67af0-8c30-449e-8e8b-ad334ec8d88c

all.gyp

@@ -3,9 +3,6 @@
 # found in the LICENSE file.
 
 {
-  'includes': [
-    'common.gypi',
-  ],
   'targets': [
     {
       'target_name': 'All',

common.gypi

@@ -2,6 +2,9 @@
 # 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': {
     # .gyp files should set chromium_code to 1 if they build Chromium-specific

gyp_chromium

@@ -0,0 +1,37 @@
+#!/usr/bin/python
+
+# This script is wrapper for Chromium that adds some support for how GYP
+# is invoked by Chromium beyond what can be done it the gclient hooks.
+
+import glob
+import os
+import shlex
+import sys
+
+print 'Updating projects from gyp files...'
+
+try:
+  import gyp
+except ImportError, e:
+  sys.path.append(os.path.join(os.path.dirname(sys.argv[0]), '../tools/gyp/pylib'))
+  import gyp
+
+if __name__ == '__main__':
+  args = sys.argv[1:]
+
+  # If we didn't get a file, check an env var, and then fall back to
+  # assuming 'src/build/all.gyp'
+  if len(args) == 0:
+    args += shlex.split(os.environ.get('CHROMIUM_GYP_FILE',
+                                       'src/build/all.gyp'))
+
+  # Always include gyp_chromium.gypi
+  args += ['-I', os.path.join(os.path.dirname(sys.argv[0]),'common.gypi')]
+  
+  # Optionally add supplemental .gypi files if present.
+  supplements = glob.glob('src/*/supplement.gypi')
+  for supplement in supplements:
+    args += ['-I', supplement]
+
+  # Off we go...
+  sys.exit(gyp.main(args))

linux/system.gyp

@@ -3,18 +3,18 @@
 # found in the LICENSE file.
 
 {
-  'variables' : {
-    'includes': [
-      '../common.gypi',
-    ],
   'conditions': [
     ['sysroot!=""', {
+      'variables': {
         'pkg-config': './pkg-config-wrapper "<(sysroot)"',
+      },
     }, {
+      'variables': {
         'pkg-config': 'pkg-config'
+      },
     }],
   ],
-  },
+  
   'targets': [
     {
       'target_name': 'gtk',

temp_gyp/googleurl.gyp

@@ -7,9 +7,6 @@
   'variables': {
     'chromium_code': 1,
   },
-  'includes': [
-    '../common.gypi',
-  ],
   'targets': [
     {
       'target_name': 'googleurl',

temp_gyp/pdfsqueeze.gyp

@@ -3,9 +3,6 @@
 # found in the LICENSE file.
 
 {
-  'includes': [
-    '../common.gypi',
-  ],
   'targets': [
     {
       'target_name': 'pdfsqueeze',

util/build_util.gyp

@@ -3,9 +3,6 @@
 # found in the LICENSE file.
 
 {
-  'includes': [
-    '../common.gypi',
-  ],
   'targets': [
     {
       'target_name': 'lastchange',

win/system.gyp

@@ -3,9 +3,6 @@
 # found in the LICENSE file.
 
 {
-  'includes': [
-    '../common.gypi',
-  ],
   'targets': [
     {
       'target_name': 'cygwin',