Make WebView respond to device scale change

content/browser/android/content_view_core_impl.cc

Index: content/browser/android/content_view_core_impl.cc
diff --git a/content/browser/android/content_view_core_impl.cc b/content/browser/android/content_view_core_impl.cc
index bee676ccad0a560288c9ea6fa10aa8d949b1b53b..b42483def0ae467abfa3ed0f312f4c642ac99104 100644
--- a/content/browser/android/content_view_core_impl.cc
+++ b/content/browser/android/content_view_core_impl.cc
@@ -429,8 +429,7 @@ void ContentViewCoreImpl::UpdateFrameInfo(
   if (obj.is_null() || !view_.GetWindowAndroid())
     return;
 
-  view_.GetWindowAndroid()->set_content_offset(
-      gfx::ScaleVector2d(content_offset, dpi_scale_));
+  view_.GetWindowAndroid()->set_content_offset(content_offset);

[boliu, 2016/08/16 15:03:03]

this change and it's fallout can be in a separate CL that's landed first

[Tima Vaisburd, 2016/08/16 20:55:28]

Created https://codereview.chromium.org/2249243002/

 
   page_scale_ = page_scale_factor;
 
@@ -909,6 +908,13 @@ void ContentViewCoreImpl::SetFocus(JNIEnv* env,
   SetFocusInternal(focused);
 }
 
+void ContentViewCoreImpl::SetDeviceScaleFactor(JNIEnv* env,
+                                               const JavaParamRef<jobject>& obj,
+                                               jfloat device_scale) {
+  DVLOG(1) << __FUNCTION__ << " " << device_scale;
+  dpi_scale_ = device_scale;

[boliu, 2016/08/16 15:03:03]

what about all the places where dpi_scale() is called? that's a lot of places

+}
+
 void ContentViewCoreImpl::SetFocusInternal(bool focused) {
   if (!GetRenderWidgetHostViewAndroid())
     return;