[DevTools] Handle emulation in embedder, call into web API.

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.
 
 {
   'dependencies': [
     '../base/base.gyp:base_static',
     '../crypto/crypto.gyp:crypto',
     '../device/vibration/vibration.gyp:device_vibration',
     '../device/vibration/vibration.gyp:device_vibration_mojo_bindings',
@@ skipping 1697 matching lines @@
         '../third_party/leveldatabase/leveldatabase.gyp:leveldatabase',
         '../third_party/mojo/mojo_public.gyp:mojo_cpp_bindings',
         '../third_party/mojo/mojo_public.gyp:mojo_js_bindings',
         '../ui/surface/surface.gyp:surface',
         '../ui/touch_selection/ui_touch_selection.gyp:ui_touch_selection',
       ],
       'export_dependent_settings': [
         '../third_party/mojo/mojo_public.gyp:mojo_cpp_bindings',
       ],
     }],
+    ['debug_devtools==1', {
+      'defines': [
+        'DEBUG_DEVTOOLS=1',
+      ],
+    }],
     ['enable_basic_printing==1 or enable_print_preview==1', {
       'dependencies': [
         '../printing/printing.gyp:printing',
       ],
     }],
     ['OS!="ios" and chrome_multiple_dll!=1', {
       'dependencies': [
         '../third_party/WebKit/public/blink.gyp:blink',
       ],
     }],
@@ skipping 262 matching lines @@
         'browser/media/media_web_contents_observer.h',
       ],
     }],
     ['OS == "linux" and use_openssl==1', {
       'dependencies': [
         '../third_party/boringssl/boringssl.gyp:boringssl',
       ],
     }],
   ],
 }