[DeviceLight] Add Layout support

content/test/layouttest_support.cc

Index: content/test/layouttest_support.cc
diff --git a/content/test/layouttest_support.cc b/content/test/layouttest_support.cc
index bbb57addbd3037bff44a07eff97527f3b32c5e6d..09c15a3469b62ebe60a0ff15415ab2bae876360b 100644
--- a/content/test/layouttest_support.cc
+++ b/content/test/layouttest_support.cc
@@ -86,6 +86,10 @@ void SetMockGamepadProvider(RendererGamepadProvider* provider) {
       set_gamepad_provider(provider);
 }
 
+void SetMockDeviceLightData(const double data) {
+  RendererWebKitPlatformSupportImpl::SetMockDeviceLightDataForTesting(data);
+}
+
 void SetMockDeviceMotionData(const WebDeviceMotionData& data) {
   RendererWebKitPlatformSupportImpl::SetMockDeviceMotionDataForTesting(data);
 }