Fix link highlights on links that contain images.

LayoutTests/compositing/gestures/resources/link-highlight-style.css

Index: LayoutTests/compositing/gestures/resources/link-highlight-style.css
diff --git a/LayoutTests/compositing/gestures/resources/link-highlight-style.css b/LayoutTests/compositing/gestures/resources/link-highlight-style.css
index e0d4dc73f7118609df81542557e5e7eec039ad4a..7e79d8b0b8416ccfcca4f2d17c5d82dcdcd754ff 100644
--- a/LayoutTests/compositing/gestures/resources/link-highlight-style.css
+++ b/LayoutTests/compositing/gestures/resources/link-highlight-style.css
@@ -38,6 +38,10 @@ a.needsFix:active {
   position: absolute;
 }
 
+.squaredHighlight {
+  -webkit-border-radius: 0px;
+}
+
 .composited {
   -webkit-transform: translateZ(0);
 }