[MD extensions] adjust paper-icon-button-light ripple sizes

This CL removes some CSS overrides that were making
paper-icon-button-light ripple sizes incorrect. So this fix is to remove
the overrides.

(relates to 746584)

Bug: 746584
Cq-Include-Trybots: master.tryserver.chromium.linux:closure_compilation
Change-Id: I88e1bae2eed231e6dd5b6a6f0e78405e5e220a64
Reviewed-on: https://chromium-review.googlesource.com/599070Reviewed-by: Scott Chen <scottchen@chromium.org>
Commit-Queue: Dave Schuyler <dschuyler@chromium.org>
Cr-Commit-Position: refs/heads/master@{#491832}

chrome/browser/resources/md_extensions/item.html

@@ -145,7 +145,7 @@
       }
 
       paper-toggle-button {
-        -webkit-margin-end: 8px; /* Avoid ripple from overlapping container. */
+        -webkit-margin-end: 8px;  /* Avoid ripple from overlapping container. */
         cursor: pointer;
       }
 
@@ -154,10 +154,7 @@
       }
 
       #dev-reload-button {
-        -webkit-margin-end: 20px;
-        height: 20px;
-        padding: 0;
-        width: 20px;
+        -webkit-margin-end: 12px;
       }
 
       #warnings {

chrome/browser/resources/md_extensions/shortcut_input.html

@@ -30,12 +30,9 @@
       }
 
       #clear {
-        bottom: 6px;
-        height: 16px;
-        padding: 0;
+        bottom: -4px;
         position: absolute;
-        right: 0;
-        width: 16px;
+        right: -8px;
       }
 
     </style>