Canvas2d: The control in hit region should be a canvas fallback element.

third_party/WebKit/Source/modules/canvas2d/CanvasRenderingContext2D.cpp

Index: third_party/WebKit/Source/modules/canvas2d/CanvasRenderingContext2D.cpp
diff --git a/third_party/WebKit/Source/modules/canvas2d/CanvasRenderingContext2D.cpp b/third_party/WebKit/Source/modules/canvas2d/CanvasRenderingContext2D.cpp
index a2afb9ed6baf517cde36048cb217bce2c63df9b6..f9db4cf808fc28ae868126c5ae87fe8477c24efc 100644
--- a/third_party/WebKit/Source/modules/canvas2d/CanvasRenderingContext2D.cpp
+++ b/third_party/WebKit/Source/modules/canvas2d/CanvasRenderingContext2D.cpp
@@ -2234,6 +2234,11 @@ void CanvasRenderingContext2D::addHitRegion(const HitRegionOptions& options, Exc
         return;
     }
 
+    if (options.control() && !canvas()->isSupportedInteractiveCanvasFallback(*options.control())) {
+        exceptionState.throwDOMException(NotSupportedError, "The control is neither null nor a supported interactive canvas fallback element.");
+        return;
+    }
+
     Path hitRegionPath = options.hasPath() ? options.path()->path() : m_path;
 
     SkCanvas* c = drawingCanvas();