MD Settings: add a <controlled-button> that uses prefs to disable itself

chrome/browser/resources/settings/controls/controlled_button.html

Index: chrome/browser/resources/settings/controls/controlled_button.html
diff --git a/chrome/browser/resources/settings/controls/controlled_button.html b/chrome/browser/resources/settings/controls/controlled_button.html
new file mode 100644
index 0000000000000000000000000000000000000000..8626343fcbcaee5962ed2b7309306c9cd998c450
--- /dev/null
+++ b/chrome/browser/resources/settings/controls/controlled_button.html
@@ -0,0 +1,26 @@
+<link rel="import" href="chrome://resources/html/polymer.html">
+<link rel="import" href="chrome://resources/polymer/v1_0/paper-button/paper-button.html">
+<link rel="import" href="chrome://resources/cr_elements/policy/cr_policy_pref_behavior.html">
+<link rel="import" href="chrome://resources/cr_elements/policy/cr_policy_pref_indicator.html">
+<link rel="import" href="/controls/pref_control_behavior.html">
+<link rel="import" href="/settings_shared_css.html">
+
+<dom-module id="controlled-button">
+  <link rel="import" type="css" href="chrome://resources/cr_elements/shared.css">
+  <template>
+    <style include="settings-shared">
+      cr-policy-pref-indicator {
+        -webkit-margin-start: var(--checkbox-spacing);
+      }
+    </style>
+
+    <paper-button disabled="[[disabled_]]">

[stevenjb, 2016/07/26 16:19:34]

'disabled_' confused me for a bit, maybe 'prefDisabled_' or 'disabledByPref_'?

[Dan Beam, 2016/07/26 19:36:50]

I actually changed to "disabled" as it matches a :host([disabled]) {
pointer-events: none; } rule in cr_elements/shared.css when reflected to an
attribute on the host

+      <content></content>
+    </paper-button>
+
+    <template is="dom-if" if="[[disabled_]]">
+      <cr-policy-pref-indicator pref="[[pref]]"></cr-policy-pref-indicator>
+    </template>
+  </template>
+  <script src="/controls/controlled_button.js"></script>
+</dom-module>