DevTools: render category filters in a way that they don't clash.

Source/devtools/front_end/ui/toolbar.css

Index: Source/devtools/front_end/ui/toolbar.css
diff --git a/Source/devtools/front_end/ui/toolbar.css b/Source/devtools/front_end/ui/toolbar.css
index d4c739f778ca4a785a8b6d37ae64c850e1eec171..829d9f3615c2a6e043384abbcdf43473bdb48ff2 100644
--- a/Source/devtools/front_end/ui/toolbar.css
+++ b/Source/devtools/front_end/ui/toolbar.css
@@ -124,7 +124,7 @@ button.toolbar-item {
 }
 
 :host-context(.material) button.toolbar-item:hover {
-    background-color: rgba(105, 105, 105, 0.1);
+    background-color: #eee;
 }
 
 button.toolbar-item.toggled-on .glyph {
@@ -449,6 +449,10 @@ button.record-toolbar-item.toggled-on .glyph {
     background-color: rgb(66, 129, 235);
 }
 
+.filter-toolbar-item.toggled-shown {
+    background-color: rgba(105, 105, 105, 0.1);
+}
+
 .filter-toolbar-item.toggled-active .glyph {
     background-color: rgb(216, 0, 0);
 }