DevTools: convert a few more icons to UI.Icon.

third_party/WebKit/Source/devtools/front_end/console/consoleView.css

Index: third_party/WebKit/Source/devtools/front_end/console/consoleView.css
diff --git a/third_party/WebKit/Source/devtools/front_end/console/consoleView.css b/third_party/WebKit/Source/devtools/front_end/console/consoleView.css
index 69646aa7c8ae965aad653db6ac773ce7f1a44905..6d7e9f8ba8b01c64a090a5ee0a3a34a09ba143b3 100644
--- a/third_party/WebKit/Source/devtools/front_end/console/consoleView.css
+++ b/third_party/WebKit/Source/devtools/front_end/console/consoleView.css
@@ -367,27 +367,6 @@
     flex: none;
 }
 
-.console-message-stack-trace-toggle .console-message-text::before {
-    content: " ";
-    -webkit-user-select: none;
-    -webkit-mask-image: url(Images/toolbarButtonGlyphs.png);
-    -webkit-mask-size: 352px 168px;
-    color: transparent;
-    text-shadow: none;
-    padding-right: 8px;
-    height: 12px;
+.stack-trace-expand-icon {
     background-color: rgb(110, 110, 110);

[dgozman, 2016/12/14 19:18:25]

Can we make this background color default? That would be beautiful, since nobody
will have to need anything about the icon!

[lushnikov, 2016/12/14 22:02:54]

I'll keep this as-is since this would break dark theme

-    width: 12px;
-    flex: none;
-    -webkit-mask-position: -4px -96px;
-}
-
-@media (-webkit-min-device-pixel-ratio: 1.1) {
-.console-message-stack-trace-toggle .console-message-text::before {
-    -webkit-mask-image: url(Images/toolbarButtonGlyphs_2x.png);
-}
-} /* media */
-
-.console-message-stack-trace-toggle.expanded .console-message-text::before {
-    -webkit-mask-position: -20px -96px;
 }