(blink) Propagate scrolling/marginwidth/marginheight property values to child frame.

Source/core/loader/FrameFetchContextTest.cpp

Index: Source/core/loader/FrameFetchContextTest.cpp
diff --git a/Source/core/loader/FrameFetchContextTest.cpp b/Source/core/loader/FrameFetchContextTest.cpp
index f1aef3701849bd1e6c611d6eaccdfb57978544e1..ecac5a99364b2972f61ca35e6b2d040cfbd78d7e 100644
--- a/Source/core/loader/FrameFetchContextTest.cpp
+++ b/Source/core/loader/FrameFetchContextTest.cpp
@@ -85,6 +85,9 @@ public:
     SandboxFlags sandboxFlags() const override { return SandboxNone; }
     void dispatchLoad() override { }
     void renderFallbackContent() override { }
+    ScrollbarMode scrollingMode() const override { return ScrollbarAuto; }
+    int marginWidth() const override { return -1; }
+    int marginHeight() const override { return -1; }
 };
 
 class FrameFetchContextTest : public ::testing::Test {