Include EXT_window_rectangles API

include/gpu/GrCaps.h

Index: include/gpu/GrCaps.h
diff --git a/include/gpu/GrCaps.h b/include/gpu/GrCaps.h
index c6b535d0bba9bad4e63eaea8004cca5ba0fa755d..924546f91ca65a4960f4167537c8b84218f9e5f2 100644
--- a/include/gpu/GrCaps.h
+++ b/include/gpu/GrCaps.h
@@ -264,6 +264,7 @@ public:
         }
     }
 
+    int maxWindowRectangles() const { return fMaxWindowRectangles; }
 
     virtual bool isConfigTexturable(GrPixelConfig config) const = 0;
     virtual bool isConfigRenderable(GrPixelConfig config, bool withMSAA) const = 0;
@@ -340,6 +341,7 @@ protected:
     int fMaxColorSampleCount;
     int fMaxStencilSampleCount;
     int fMaxRasterSamples;
+    int fMaxWindowRectangles;
 
 private:
     virtual void onApplyOptionsOverrides(const GrContextOptions&) {};