Changed VRLayer's left/rightBounds to match the spec

third_party/WebKit/Source/modules/vr/VRLayer.idl

Index: third_party/WebKit/Source/modules/vr/VRLayer.idl
diff --git a/third_party/WebKit/Source/modules/vr/VRLayer.idl b/third_party/WebKit/Source/modules/vr/VRLayer.idl
index c31d345bb5b8f7e874301402fc417ff7939f99a7..9e9a6a53cdbd1788b0963de27e5a249deed6c87f 100644
--- a/third_party/WebKit/Source/modules/vr/VRLayer.idl
+++ b/third_party/WebKit/Source/modules/vr/VRLayer.idl
@@ -17,6 +17,6 @@ typedef HTMLCanvasElement VRSource;
   // [1] top offset of the bounds (0.0 - 1.0)
   // [2] width of the bounds (0.0 - 1.0)
   // [3] height of the bounds (0.0 - 1.0)
-  sequence<float>? leftBounds; //= [0.0, 0.0, 0.5, 1.0];
-  sequence<float>? rightBounds; //= [0.5, 0.0, 0.5, 1.0];
+  sequence<float> leftBounds = []; //= [0.0, 0.0, 0.5, 1.0];
+  sequence<float> rightBounds = []; //= [0.5, 0.0, 0.5, 1.0];
 };