DevTools: get rid of deviceMetics settings.

Source/devtools/front_end/responsiveDesignView.css

Index: Source/devtools/front_end/responsiveDesignView.css
diff --git a/Source/devtools/front_end/responsiveDesignView.css b/Source/devtools/front_end/responsiveDesignView.css
index fcea798c42c3b1c73f1f8e04b62aa68fe3222c28..5187ac46dc337fbd988053f95c7bc05a9e1a5a1a 100644
--- a/Source/devtools/front_end/responsiveDesignView.css
+++ b/Source/devtools/front_end/responsiveDesignView.css
@@ -101,14 +101,18 @@
     padding: 3px;
 }
 
+.responsive-design-toolbar input[type='text']:disabled {
+    opacity: 0.6;
+}
+
 .responsive-design-toolbar input[type='checkbox'] {
     background: none;
     margin: 0;
-    margin-right: 3px;
+    margin-right: 5px;
 }
 
 .responsive-design-toolbar input[type='checkbox']:after {
-    content:'\2714';
+    content:'\2713';
     color: transparent;
     line-height: 10px;
     position: absolute;