Replace RectVectors with SkRegions in Decoder.

remoting/base/decoder_row_based.cc

Index: remoting/base/decoder_row_based.cc
diff --git a/remoting/base/decoder_row_based.cc b/remoting/base/decoder_row_based.cc
index da65079ddaa7cc0287abee367b3b0dfbf2c2ad0a..d1b2cb6c61b7ca5ec551cfb43cc52baf4b4c5a2a 100644
--- a/remoting/base/decoder_row_based.cc
+++ b/remoting/base/decoder_row_based.cc
@@ -44,7 +44,7 @@ void DecoderRowBased::Reset() {
   frame_ = NULL;
   decompressor_->Reset();
   state_ = kUninitialized;
-  updated_rects_.clear();
+  updated_region_.setEmpty();
 }
 
 bool DecoderRowBased::IsReadyForData() {
@@ -128,7 +128,7 @@ Decoder::DecodeResult DecoderRowBased::DecodePacket(const VideoPacket* packet) {
       return DECODE_ERROR;
     }
 
-    updated_rects_.push_back(clip_);
+    updated_region_.op(clip_, SkRegion::kUnion_Op);
     decompressor_->Reset();
   }
 
@@ -186,9 +186,9 @@ void DecoderRowBased::UpdateStateForPacket(const VideoPacket* packet) {
   return;
 }
 
-void DecoderRowBased::GetUpdatedRects(RectVector* rects) {
-  rects->swap(updated_rects_);
-  updated_rects_.clear();
+void DecoderRowBased::GetUpdatedRegion(SkRegion* region) {
+  region->swap(updated_region_);
+  updated_region_.setEmpty();
 }
 
 VideoPacketFormat::Encoding DecoderRowBased::Encoding() {