Add a gyp flag to allow removing dependency on ppapi.

chrome/chrome_browser.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.
 
 {
   'targets': [
     {
       'target_name': 'browser',
       'type': 'static_library',
@@ skipping 2200 matching lines @@
             'autofill_regexes',
             'browser/performance_monitor/performance_monitor.gyp:performance_monitor',
             'browser_extensions',
             'common/extensions/api/api.gyp:api',
             'debugger',
             'installer_util',
             'sync_file_system_proto',
             '../cc/cc.gyp:cc',
             '../content/content.gyp:navigation_interception',
             '../net/net.gyp:net_with_v8',
-            '../ppapi/ppapi_internal.gyp:ppapi_ipc',  # For PpapiMsg_LoadPlugin
             '../printing/printing.gyp:printing',
             '../third_party/adobe/flash/flash_player.gyp:flapper_version_h',
             '../third_party/expat/expat.gyp:expat',
             '../third_party/hunspell/hunspell.gyp:hunspell',
             '../third_party/leveldatabase/leveldatabase.gyp:leveldatabase',
             '../third_party/libjingle/libjingle.gyp:libjingle',
             '../third_party/libphonenumber/libphonenumber.gyp:libphonenumber',
             '../third_party/npapi/npapi.gyp:npapi',
             '../third_party/re2/re2.gyp:re2',
             '../ui/gl/gl.gyp:gl',
@@ skipping 129 matching lines @@
             ['exclude', 'browser/value_store/policy_value_store.cc'],
             ['exclude', 'browser/value_store/policy_value_store.h'],
             ['include', 'browser/policy/policy_map.cc'],
             ['include', 'browser/policy/policy_map.h'],
             ['include', 'browser/policy/policy_service.cc'],
             ['include', 'browser/policy/policy_service.h'],
             ['include', 'browser/policy/policy_service_stub.cc'],
             ['include', 'browser/policy/policy_service_stub.h'],
           ],
         }],
+        ['enable_plugins==1', {
+          'dependencies': [
+            '../ppapi/ppapi_internal.gyp:ppapi_ipc',
+          ],
+        }, {  # enable_plugins==0
+          'sources/': [
+            ['exclude', '^browser/pepper_'],
+            ['exclude', '^browser/renderer_host/pepper/'],
+          ],
+        }],
         ['safe_browsing==1', {
           'defines': [
             'FULL_SAFE_BROWSING',
           ],
         }],
         ['safe_browsing==2', {
           'defines': [
             'MOBILE_SAFE_BROWSING',
           ],
           'dependencies!': [
@@ skipping 742 matching lines @@
             'proto_in_dir': '../third_party/cros_system_api/dbus',
             'proto_out_dir': 'chrome/browser/media_transfer_protocol',
           },
           'includes': ['../build/protoc.gypi'],
         },
       ],
      },
     ],
   ],
 }