[DevTools] Turn WebInspector.Panel into a web component.

third_party/WebKit/Source/devtools/front_end/ui/inspectorStyle.css

Index: third_party/WebKit/Source/devtools/front_end/ui/inspectorStyle.css
diff --git a/third_party/WebKit/Source/devtools/front_end/ui/inspectorStyle.css b/third_party/WebKit/Source/devtools/front_end/ui/inspectorStyle.css
index e88c716086a2128ceecc2f5a93b9b8750ccef6e6..128fe939b381c57a94164723e5fb65015cf8fdaa 100644
--- a/third_party/WebKit/Source/devtools/front_end/ui/inspectorStyle.css
+++ b/third_party/WebKit/Source/devtools/front_end/ui/inspectorStyle.css
@@ -59,30 +59,3 @@ body {
 .platform-windows {
     font-family: 'Segoe UI', Tahoma, sans-serif;
 }
-
-.panel {
-    display: flex;
-    overflow: hidden;
-    position: absolute;
-    top: 0;
-    left: 0;
-    right: 0;
-    bottom: 0;
-    z-index: 0;
-}
-
-.panel-sidebar {
-    overflow-x: hidden;
-    background-color: #f3f3f3;
-}
-
-iframe.extension {
-    flex: auto;
-    width: 100%;
-    height: 100%;
-}
-
-iframe.panel.extension {
-    display: block;
-    height: 100%;
-}