Fix an issue that an invalid surface could be passed to MediaPlayerBridge

ui/gl/android/scoped_java_surface.h

Index: ui/gl/android/scoped_java_surface.h
diff --git a/ui/gl/android/scoped_java_surface.h b/ui/gl/android/scoped_java_surface.h
index 54ed2a45190288f62a93e1018b8b9d0e4117055e..38447f92924890ca5d5b0e0d9e25da401129edf0 100644
--- a/ui/gl/android/scoped_java_surface.h
+++ b/ui/gl/android/scoped_java_surface.h
@@ -42,10 +42,13 @@ class GL_EXPORT ScopedJavaSurface {
 
   ~ScopedJavaSurface();
 
-  // Check whether the surface is an empty one.
+  // Checks whether the surface is an empty one.
   bool IsEmpty() const;
 
-  // Check whether the surface is hardware protected so that no readback is
+  // Checks whether the surface is valid.
+  bool IsValid() const;
+
+  // Checks whether the surface is hardware protected so that no readback is
   // possible.
   bool is_protected() const { return is_protected_; }