Serialize PictureLayer properties.

cc/proto/layer.proto

Index: cc/proto/layer.proto
diff --git a/cc/proto/layer.proto b/cc/proto/layer.proto
index 914ff8a9247571b7c903c25903fcd50c3f6f93e6..9308b5d78ad89f6a63e1ea8a62d197e9340a1518 100644
--- a/cc/proto/layer.proto
+++ b/cc/proto/layer.proto
@@ -4,6 +4,11 @@
 
 syntax = "proto2";
 
+import "display_list_recording_source.proto";
+import "size.proto";
+import "rect.proto";
+import "region.proto";
+
 package cc.proto;
 
 option optimize_for = LITE_RUNTIME;
@@ -11,7 +16,9 @@ option optimize_for = LITE_RUNTIME;
 // Identifies the type of cc:Layer a LayerNode represents. It is used to
 // facilitate reconstruction of a Layer of the correct type on the client.
 enum LayerType {
-  Base = 1;
+  UNKNOWN = 0;
+  LAYER = 1;
+  PICTURE_LAYER = 2;
 
   // TODO(nyquist): Add the rest of the necessary LayerTypes.
 };
@@ -47,8 +54,23 @@ message LayerProperties {
   // The Layer base class and each descendant have different proto messages
   // for their specific properties.
   optional BaseLayerProperties base = 5;
+
+  // Only one of these fields may be set per LayerProperties.
+  // TODO(dtrainor): use a 'oneof' union when it's supported in Chromium.  See
+  // crbug.com/570371.
+  optional PictureLayerProperties picture = 6;
 }
 
 message BaseLayerProperties {
   // TODO(nyquist): Add all the required properties below. Huzzah!
 }
+
+message PictureLayerProperties {
+  optional DisplayListRecordingSource recording_source = 1;
+  optional Region invalidation = 2;
+  optional Rect last_updated_visible_layer_rect = 3;
+  optional bool is_mask = 4;
+  optional bool nearest_neighbor = 5;
+
+  optional int64 update_source_frame_number = 6;
+}