Enforce constant size and device scale factor for surfaces

android_webview/browser/hardware_renderer.cc

Index: android_webview/browser/hardware_renderer.cc
diff --git a/android_webview/browser/hardware_renderer.cc b/android_webview/browser/hardware_renderer.cc
index 186e744e6bb45868b2bbaf39013016412f5037fe..c988cc58451d77b577ce97e2e70d6c788bae6508 100644
--- a/android_webview/browser/hardware_renderer.cc
+++ b/android_webview/browser/hardware_renderer.cc
@@ -118,14 +118,17 @@ void HardwareRenderer::DrawGL(AwDrawGLInfo* draw_info) {
     std::unique_ptr<cc::CompositorFrame> child_compositor_frame =
         std::move(child_frame_->frame);
 
+    float device_scale_factor =
+        child_compositor_frame->metadata.device_scale_factor;
     gfx::Size frame_size =
         child_compositor_frame->render_pass_list.back()->output_rect.size();
-    bool size_changed = frame_size != frame_size_;
-    frame_size_ = frame_size;
-    if (!child_id_.is_valid() || size_changed) {
+    if (!child_id_.is_valid() || surface_size_ != frame_size ||
+        device_scale_factor_ != device_scale_factor) {
       if (child_id_.is_valid())
         DestroySurface();
       AllocateSurface();
+      surface_size_ = frame_size;
+      device_scale_factor_ = device_scale_factor;
     }
 
     support_->SubmitCompositorFrame(child_id_,
@@ -153,7 +156,7 @@ void HardwareRenderer::DrawGL(AwDrawGLInfo* draw_info) {
   gfx::Rect clip(draw_info->clip_left, draw_info->clip_top,
                  draw_info->clip_right - draw_info->clip_left,
                  draw_info->clip_bottom - draw_info->clip_top);
-  surfaces_->DrawAndSwap(viewport, clip, transform, frame_size_,
+  surfaces_->DrawAndSwap(viewport, clip, transform, surface_size_,
                          cc::SurfaceId(frame_sink_id_, child_id_));
 }