add drawArraysInstanced to caps

include/gpu/GrCaps.h

Index: include/gpu/GrCaps.h
diff --git a/include/gpu/GrCaps.h b/include/gpu/GrCaps.h
index 9ad20e53e41f3d123b3249f4832c760201109b78..29c9603fd712bdbe6a16fed661c939dc50bb7dcb 100644
--- a/include/gpu/GrCaps.h
+++ b/include/gpu/GrCaps.h
@@ -216,6 +216,10 @@ public:
         return fGeometryBufferMapThreshold;
     }
 
+    bool drawArraysInstancedSupport() const {

[bsalomon, 2015/06/26 13:37:14]

I really don't like having GLisms bleed into GrCaps (drawArraysInstanced). Can
we keep this GrGLCaps for now? Or can we think of what the high level thing
we're trying to capture as a capability is (e.g. supportsInstancedDraws()).

Also, we aren't grabbing the function pointers in the interface. Does this
really need to be in caps at all at this point? Maybe we should wait until we
figure out how to expose this at the Gr level?

+        return fDrawArraysInstancedSupport;
+    }
+
 protected:
     /** Subclasses must call this at the end of their constructors in order to apply caps
         overrides requested by the client. Note that overrides will only reduce the caps never
@@ -235,6 +239,7 @@ protected:
     bool fCompressedTexSubImageSupport               : 1;
     bool fOversizedStencilSupport                    : 1;
     bool fTextureBarrierSupport                      : 1;
+    bool fDrawArraysInstancedSupport                 : 1;
 
     // Driver workaround
     bool fUseDrawInsteadOfClear                      : 1;