Force DC overlay for hardware protected video with any blend mode

For protected video, it must be protected and decoded by hardware through
Direct Composition overlay swap chain. It's fine if the blend mode is not
handled correctly.

Bug:843814

Change-Id: I07c3ed40716fd9979f3f83c395a593fa1f0b5dd5
Reviewed-on: https://chromium-review.googlesource.com/c/1357647Reviewed-by: Sunny Sachanandani <sunnyps@chromium.org>
Reviewed-by: Zhenyao Mo <zmo@chromium.org>
Commit-Queue: Maggie Chen <magchen@chromium.org>
Cr-Commit-Position: refs/heads/master@{#612921}

components/viz/service/display/dc_layer_overlay.cc

@@ -121,8 +121,6 @@ DCLayerOverlayProcessor::DCLayerResult DCLayerOverlayProcessor::FromDrawQuad(
     QuadList::ConstIterator quad_list_begin,
     QuadList::ConstIterator quad,
     DCLayerOverlay* dc_layer_overlay) {
-  if (quad->shared_quad_state->blend_mode != SkBlendMode::kSrcOver)
-    return DC_LAYER_FAILED_QUAD_BLEND_MODE;
 
   DCLayerResult result;
   switch (quad->material) {
@@ -137,6 +135,12 @@ DCLayerOverlayProcessor::DCLayerResult DCLayerOverlayProcessor::FromDrawQuad(
   if (result != DC_LAYER_SUCCESS)
     return result;
 
+  // Hardware protected video must use Direct Composition Overlay
+  if (quad->shared_quad_state->blend_mode != SkBlendMode::kSrcOver &&
+      dc_layer_overlay->protected_video_type !=
+          ui::ProtectedVideoType::kHardwareProtected)
+    return DC_LAYER_FAILED_QUAD_BLEND_MODE;
+
   // To support software protected video on machines without hardware overlay
   // capability. Don't do dc layer overlay if no hardware support.
   if (!has_hw_overlay_support_ &&