Update "Predict network actions" UI setting.

chrome/browser/resources/options/browser_options.js

Index: chrome/browser/resources/options/browser_options.js
diff --git a/chrome/browser/resources/options/browser_options.js b/chrome/browser/resources/options/browser_options.js
index 49ddceb11051ff7619330d037dbf8c48e17ce25b..c1f3e5f2817f19a6c74963a7793eae179de91520 100644
--- a/chrome/browser/resources/options/browser_options.js
+++ b/chrome/browser/resources/options/browser_options.js
@@ -7,6 +7,12 @@ cr.define('options', function() {
   var ArrayDataModel = cr.ui.ArrayDataModel;
   var RepeatingButton = cr.ui.RepeatingButton;
   var HotwordSearchSettingIndicator = options.HotwordSearchSettingIndicator;
+  var NetworkPredictionOptions = {
+    ALWAYS: 0,
+    WIFI_ONLY: 1,
+    NEVER: 2,
+    UNSET: 3

[stevenjb, 2014/07/30 18:03:29]

Unused?

[Bence, 2014/08/01 14:36:46]

Done.

+  };
 
   //
   // BrowserOptions class
@@ -348,6 +354,26 @@ cr.define('options', function() {
               [String(event.currentTarget.checked)]);
         };
       }
+      $('networkPredictionOptionsBool').onchange = function(event) {
+        var value = (event.target.checked ?
+            NetworkPredictionOptions.WIFI_ONLY :
+            NetworkPredictionOptions.NEVER);
+        var metric = event.target.metric;
+        Preferences.setIntegerPref(
+            'net.network_prediction_options',
+            value,
+            true,
+            metric);
+      };
+      $('networkPredictionOptionsTristate').onchange = function(event) {
+        var value = event.target.options[event.target.selectedIndex].value;

[stevenjb, 2014/07/30 18:03:29]

nit: assert value <= NEVER

[Bence, 2014/08/01 14:36:47]

Moot: this function is removed as a result of UI review.

+        var metric = event.target.metric;
+        Preferences.setIntegerPref(
+            'net.network_prediction_options',
+            value,
+            true,
+            metric);
+      };
 
       // Bluetooth (CrOS only).
       if (cr.isChromeOS) {
@@ -1456,6 +1482,43 @@ cr.define('options', function() {
     },
 
     /**
+     * Set visibility of network prediction controls based on current connection
+     * type.
+     *
+     * @param {Object} pref Information about network connection.
+     * @param {boolean} pref.onCellularNetwork True if current network
+     * connection is cellular.
+     * @private
+     */
+    setNetworkPredictionVisibility_: function(pref) {
+      if (pref.onCellularNetwork) {
+        $('networkPredictionOptionsBoolDiv').hidden = true;
+        $('networkPredictionOptionsTristateDiv').hidden = false;
+      } else {
+        $('networkPredictionOptionsBoolDiv').hidden = false;
+        $('networkPredictionOptionsTristateDiv').hidden = true;
+      }
+    },
+
+    /**
+     * Set network prediction controls.  There is a checkbox and a dropdown
+     * menu, exactly one of which is visible.
+     *
+     * @param {Object} pref Information about network prediction options.
+     * @param {number} pref.value The value of network prediction options.
+     * @param {boolean} pref.disabled If the pref is not user modifiable.
+     * @private
+     */
+    setNetworkPredictionValue_: function(pref) {
+      var checkbox = $('networkPredictionOptionsBool');
+      checkbox.disabled = pref.disabled;
+      checkbox.checked = !(pref.value == NetworkPredictionOptions.NEVER);
+      var dropdown = $('networkPredictionOptionsTristate');
+      dropdown.disabled = pref.disabled;
+      dropdown.value = pref.value;
+    },
+
+    /**
      * Set the font size selected item. This item actually reflects two
      * preferences: the default font size and the default fixed font size.
      *
@@ -1838,6 +1901,8 @@ cr.define('options', function() {
     'setCanSetTime',
     'setFontSize',
     'setNativeThemeButtonEnabled',
+    'setNetworkPredictionValue',
+    'setNetworkPredictionVisibility',

[stevenjb, 2014/07/30 18:03:29]

Do we really need two API calls for this? It looks like we always call both?

[Bence, 2014/08/01 14:36:46]

Moot: one function is removed as the result of UI review.  FYI
setNetworkPredictionVisibility was only called when the Settings page was
displayed, setNetworkPredictionValue is called upon every value change.

     'setHighContrastCheckboxState',
     'setMetricsReportingCheckboxState',
     'setMetricsReportingSettingVisibility',