Add test configs for instanced rendering

include/gpu/GrCaps.h

Index: include/gpu/GrCaps.h
diff --git a/include/gpu/GrCaps.h b/include/gpu/GrCaps.h
index 5086d79be9e0893466db96f1ffcbdd6eb3424fcc..0f39a5e485708ea860de5e81ff4e4fb08d1ef555 100644
--- a/include/gpu/GrCaps.h
+++ b/include/gpu/GrCaps.h
@@ -174,6 +174,21 @@ public:
     bool preferVRAMUseOverFlushes() const { return fPreferVRAMUseOverFlushes; }
 
     /**
+     * Indicates the level of support for gr_instanced::* functionality. A higher level includes
+     * all functionality from the levels below it.
+     */
+    enum class InstancedSupport {
+        kNone,
+        kBasic,
+        kMultisampled,
+        kMixedSampled
+    };
+
+    InstancedSupport instancedSupport() const { return fInstancedSupport; }
+
+    bool avoidInstancedDrawsToFPTargets() const { return fAvoidInstancedDrawsToFPTargets; }
+
+    /**
      * Indicates the capabilities of the fixed function blend unit.
      */
     enum BlendEquationSupport {
@@ -307,12 +322,15 @@ protected:
     bool fUseDrawInsteadOfClear                      : 1;
     bool fUseDrawInsteadOfPartialRenderTargetWrite   : 1;
     bool fUseDrawInsteadOfAllRenderTargetWrites      : 1;
+    bool fAvoidInstancedDrawsToFPTargets             : 1;
 
     // ANGLE workaround
     bool fPreferVRAMUseOverFlushes                   : 1;
 
     bool fSampleShadingSupport                       : 1;
 
+    InstancedSupport fInstancedSupport;
+
     BlendEquationSupport fBlendEquationSupport;
     uint32_t fAdvBlendEqBlacklist;
     GR_STATIC_ASSERT(kLast_GrBlendEquation < 32);