Optimize ValidateDrawAttribs: Part 3.

This is a small optimization for the WebGL compatibility mode.
Instead of scanning the list of attributes for a Transform feedback
conflict, it can quickly check a cached mask. This should save a lot
of cycles on the fast path.

Bug: angleproject:1391
Change-Id: Icb8d095493a629dbff0e93872357e5bf7c7458ae
Reviewed-on: https://chromium-review.googlesource.com/1011236
Commit-Queue: Jamie Madill <jmadill@chromium.org>
Reviewed-by: Corentin Wallez <cwallez@chromium.org>
diff --git a/src/libANGLE/Context.cpp b/src/libANGLE/Context.cpp
index 22314ac..d99c09e 100644
--- a/src/libANGLE/Context.cpp
+++ b/src/libANGLE/Context.cpp
@@ -1012,7 +1012,7 @@
 void Context::bindVertexArray(GLuint vertexArrayHandle)
 {
     VertexArray *vertexArray = checkVertexArrayAllocation(vertexArrayHandle);
-    mGLState.setVertexArrayBinding(vertexArray);
+    mGLState.setVertexArrayBinding(this, vertexArray);
 }
 
 void Context::bindVertexBuffer(GLuint bindingIndex,
@@ -2669,7 +2669,7 @@
     // [OpenGL ES 3.0.2] section 2.10 page 43:
     // If a vertex array object that is currently bound is deleted, the binding
     // for that object reverts to zero and the default vertex array becomes current.
-    if (mGLState.removeVertexArrayBinding(vertexArray))
+    if (mGLState.removeVertexArrayBinding(this, vertexArray))
     {
         bindVertexArray(0);
     }