Limit image filtering during scale animations

cc/playback/display_list_raster_source.cc

Index: cc/playback/display_list_raster_source.cc
diff --git a/cc/playback/display_list_raster_source.cc b/cc/playback/display_list_raster_source.cc
index 970648fbade4d25790a02b26f342a4002f9c5c62..0a8469b8783fe026bb2914996e091a90b247c828 100644
--- a/cc/playback/display_list_raster_source.cc
+++ b/cc/playback/display_list_raster_source.cc
@@ -47,7 +47,8 @@ DisplayListRasterSource::DisplayListRasterSource(
       slow_down_raster_scale_factor_for_debug_(
           other->slow_down_raster_scale_factor_for_debug_),
       should_attempt_to_use_distance_field_text_(false),
-      image_decode_controller_(nullptr) {
+      image_decode_controller_(nullptr),
+      image_scaling_optimization_(ImageScalingOptimization::Static) {
   // In certain cases, ThreadTaskRunnerHandle isn't set (Android Webview).
   // Don't register a dump provider in these cases.
   // TODO(ericrk): Get this working in Android Webview. crbug.com/517156
@@ -107,8 +108,12 @@ void DisplayListRasterSource::PlaybackToSharedCanvas(
     RasterCommon(&canvas, nullptr, canvas_rect, canvas_rect, contents_scale);
   } else if (display_list_->MayHaveDiscardableImages()) {
     const SkImageInfo& info = raster_canvas->imageInfo();
+    const SkFilterQuality max_quality =
+        image_scaling_optimization_ == ImageScalingOptimization::Static
+            ? kHigh_SkFilterQuality
+            : kMedium_SkFilterQuality;
     ImageHijackCanvas canvas(info.width(), info.height(),
-                             image_decode_controller_);
+                             image_decode_controller_, max_quality);
     canvas.addCanvas(raster_canvas);
 
     RasterCommon(&canvas, nullptr, canvas_rect, canvas_rect, contents_scale);
@@ -139,8 +144,12 @@ void DisplayListRasterSource::PlaybackToCanvas(
                  contents_scale);
   } else if (display_list_->MayHaveDiscardableImages()) {
     const SkImageInfo& info = raster_canvas->imageInfo();
+    const SkFilterQuality max_quality =
+        image_scaling_optimization_ == ImageScalingOptimization::Static
+            ? kHigh_SkFilterQuality
+            : kMedium_SkFilterQuality;
     ImageHijackCanvas canvas(info.width(), info.height(),
-                             image_decode_controller_);
+                             image_decode_controller_, max_quality);
     canvas.addCanvas(raster_canvas);
     RasterCommon(&canvas, nullptr, canvas_bitmap_rect, canvas_playback_rect,
                  contents_scale);
@@ -371,6 +380,11 @@ void DisplayListRasterSource::SetImageDecodeController(
   image_decode_controller_ = image_decode_controller;
 }
 
+void DisplayListRasterSource::SetImageScalingOptimization(
+    ImageScalingOptimization opt) {
+  image_scaling_optimization_ = opt;
+}
+
 bool DisplayListRasterSource::OnMemoryDump(
     const base::trace_event::MemoryDumpArgs& args,
     base::trace_event::ProcessMemoryDump* pmd) {