Move cr-button CSS to shared common.css

Bug: 992823
Change-Id: Ib1fa7a548291426068b4ecc156b10a0c1241337a
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2040797Reviewed-by: Luciano Pacheco <lucmult@chromium.org>
Commit-Queue: Alex Danilo <adanilo@chromium.org>
Cr-Commit-Position: refs/heads/master@{#739139}

ui/file_manager/file_manager/foreground/css/common.css

@@ -7,6 +7,11 @@
   display: none !important;
 }
 
+cr-button {
+  --active-bg: none;  /* prevent dark-mode activation color */
+  box-shadow: none;
+}
+
 /* "chrome-menu" class overrides some standard menu.css styles, to make custom
    menus in FileBrowser look like native ChromeOS menus. */
 

ui/file_manager/file_manager/foreground/css/file_manager.css

@@ -445,12 +445,6 @@ body[type='open-multi-file'].check-select .dialog-header {
   flex: auto;
 }
 
-/* TODO(adanilo) Move this to common.css */
-cr-button {
-  --active-bg: none;  /* prevent dark-mode activation color */
-  box-shadow: none;
-}
-
 .dialog-header cr-button,
 .dialog-header button {
   --text-color: white;