Add content renderer to the GN build

Also adds ui/native_theme, third_party/npapi, and some required mojo stuff to make it build.

BUG=
R=scottmg@chromium.org

Review URL: https://codereview.chromium.org/299113002

git-svn-id: http://src.chromium.org/svn/trunk/src/build@273079 4ff67af0-8c30-449e-8e8b-ad334ec8d88c

config/BUILD.gn

@@ -47,6 +47,11 @@ config("feature_flags") {
       "V8_DEPRECATION_WARNINGS",  # Don't use deprecated V8 APIs anywhere.
       # Temporary suppression until Blink code can be removed.
       "BLINK_SCALE_FILTERS_AT_RECORD_TIME",
+
+      # Enable a new Gamepad interface.
+      # TODO(cdumez): This is temporary and should go away once the chromium
+      # and blink interfaces are in sync, http://crbug.com/344556.
+      "ENABLE_NEW_GAMEPAD_API=1",
   ]
 
   if (cld_version > 0) {

config/features.gni

@@ -56,3 +56,7 @@ use_seccomp_bpf = (is_linux || is_android) &&
   (cpu_arch == "x86" || cpu_arch == "x64" || cpu_arch == "arm")
 
 enable_webrtc = !is_ios
+
+# Enable notifications everywhere except Android.
+# Android is http://crbug.com/115320
+enable_notifications = !is_android