add getTextureHandle to SkSurface

src/image/SkSurface.cpp

Index: src/image/SkSurface.cpp
diff --git a/src/image/SkSurface.cpp b/src/image/SkSurface.cpp
index a99997306be1b2c36557f2d06a241f78762b171f..34035a36708bbd82ccd4979ab77b28f115cf7e78 100644
--- a/src/image/SkSurface.cpp
+++ b/src/image/SkSurface.cpp
@@ -175,6 +175,10 @@ bool SkSurface::readPixels(const SkImageInfo& dstInfo, void* dstPixels, size_t d
     return this->getCanvas()->readPixels(dstInfo, dstPixels, dstRowBytes, srcX, srcY);
 }
 
+GrBackendObject SkSurface::getTextureHandle(TextureHandleAccess access) {
+    return asSB(this)->onGetTextureHandle(access);
+}
+
 //////////////////////////////////////////////////////////////////////////////////////
 
 #if !SK_SUPPORT_GPU