Add a gyp flag to allow removing dependency on ppapi.

content/content_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.
 
 {
   'variables': {
     'conditions': [
       ['chromeos==1', {
         'use_libgps%': 1,
       }, { # chromeos==0
@@ skipping 901 matching lines @@
         ['include', '^browser/speech/'],
         ['exclude', '^browser/speech/input_tag_speech_dispatcher_host\\.cc$$'],
         ['include', '^browser/user_metrics\\.cc$'],
         ['include', '^browser/web_contents/navigation_entry_impl\\.cc$'],
       ],
     }, {  # OS!="ios"
       'dependencies': [
         'browser/debugger/devtools_resources.gyp:devtools_resources',
         '../cc/cc.gyp:cc',
         '../net/net.gyp:http_server',
-        '../ppapi/ppapi_internal.gyp:ppapi_ipc',
         '../printing/printing.gyp:printing',
         '<(webkit_src_dir)/Source/WebKit/chromium/WebKit.gyp:webkit',
         '../ui/surface/surface.gyp:surface',
         '../webkit/support/webkit_support.gyp:webkit_resources',
         '../webkit/support/webkit_support.gyp:webkit_storage',
         '../webkit/support/webkit_support.gyp:webkit_strings',
       ],
     }],
     ['OS!="mac" and OS!="ios"', {
       'dependencies': [
@@ skipping 172 matching lines @@
       'sources/': [
         ['exclude', '^browser/renderer_host/image_transport_client.cc'],
         ['exclude', '^browser/renderer_host/image_transport_client.h'],
         ['exclude', '^browser/renderer_host/image_transport_factory.cc'],
         ['exclude', '^browser/renderer_host/image_transport_factory.h'],
         ['exclude', '^browser/renderer_host/render_widget_host_view_aura.cc'],
         ['exclude', '^browser/renderer_host/render_widget_host_view_aura.h'],
         ['exclude', '^browser/renderer_host/tap_suppression_controller_aura.cc'],
       ],
     }],
+    ['enable_ppapi==1', {
+      'dependencies': [
+        '../ppapi/ppapi_internal.gyp:ppapi_ipc',
+      ],
+    }, {  # enable_ppapi==0
+      'sources!': [
+        'browser/ppapi_plugin_process_host.cc',
+      ],
+      'sources/': [
+        ['exclude', '^browser/renderer_host/pepper/'],
+      ],
+    }],
     ['java_bridge==1', {
       'defines': [
         'ENABLE_JAVA_BRIDGE',
       ],
     }, {
       'sources/': [
         ['exclude', '^browser/renderer_host/java/'],
       ],
     }],
     ['input_speech==0', {
@@ skipping 10 matching lines @@
       # the USE_LIBGPS setting propagates to the "real" dependent target,
       # we use all_dependent_settings here.
       'all_dependent_settings': {
         'defines': [
           'USE_LIBGPS',
         ],
       },
     }],
   ],
 }