ES31: Add GL_ATOMIC_COUNTER_BUFFER_BINDING binding point

BUG=angleproject:1729
TEST=dEQP-GLES31.functional.state_query.integer.atomic_counter*
     dEQP-GLES31.functional.state_query.indexed.atomic_counter*
     angle_end2end_tests:AtomicCounterBufferTest

Change-Id: I059c4e22e04cedec9134ec9f631de33f77b1fbe2
Reviewed-on: https://chromium-review.googlesource.com/430959
Reviewed-by: Geoff Lang <geofflang@chromium.org>
Reviewed-by: Jamie Madill <jmadill@chromium.org>
Commit-Queue: Jamie Madill <jmadill@chromium.org>
diff --git a/src/libANGLE/ContextState.cpp b/src/libANGLE/ContextState.cpp
index 4cd11d4..4694929 100644
--- a/src/libANGLE/ContextState.cpp
+++ b/src/libANGLE/ContextState.cpp
@@ -581,6 +581,7 @@
 
     switch (pname)
     {
+        case GL_ATOMIC_COUNTER_BUFFER_BINDING:
         case GL_DRAW_INDIRECT_BUFFER_BINDING:
         case GL_MAX_FRAMEBUFFER_WIDTH:
         case GL_MAX_FRAMEBUFFER_HEIGHT:
@@ -673,11 +674,19 @@
     {
         case GL_MAX_COMPUTE_WORK_GROUP_COUNT:
         case GL_MAX_COMPUTE_WORK_GROUP_SIZE:
+        case GL_ATOMIC_COUNTER_BUFFER_BINDING:
         {
             *type      = GL_INT;
             *numParams = 1;
             return true;
         }
+        case GL_ATOMIC_COUNTER_BUFFER_START:
+        case GL_ATOMIC_COUNTER_BUFFER_SIZE:
+        {
+            *type      = GL_INT_64_ANGLEX;
+            *numParams = 1;
+            return true;
+        }
     }
 
     return false;