MD Settings: handle zoom as floats to fix ghost zoom level issue

chrome/common/extensions/api/settings_private.idl

 // Copyright 2015 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 // Use the <code>chrome.settingsPrivate</code> API to get or set preferences
 // from the settings UI.
 namespace settingsPrivate {
   // Type of a pref.
   enum PrefType { BOOLEAN, NUMBER, STRING, URL, LIST, DICTIONARY };
 
@@ skipping 39 matching lines @@
     DOMString? extensionId;
 
     // True if the pref is not controlled by a policy or user, but it can not be
     // modified (pref->IsUserModifiable() is false). Defaults to false.
     boolean? readOnly;
   };
 
   callback OnPrefSetCallback = void (boolean success);
   callback GetAllPrefsCallback = void (PrefObject[] prefs);
   callback GetPrefCallback = void (PrefObject pref);
-  callback GetDefaultZoomPercentCallback = void (long percent);
+  callback GetDefaultZoomPercentCallback = void (double percent);
   callback SetDefaultZoomPercentCallback = void (boolean success);
 
   interface Functions {
     // Sets a settings value.
     // |name|: The name of the pref.
     // |value|: The new value of the pref.
     // |pageId|: The user metrics identifier or null.
     // |callback|: The callback for whether the pref was set or not.
     static void setPref(DOMString name, any value,
         DOMString pageId, OnPrefSetCallback callback);
 
     // Gets an array of all the prefs.
     static void getAllPrefs(GetAllPrefsCallback callback);
 
     // Gets the value of a specific pref.
     static void getPref(DOMString name, GetPrefCallback callback);
 
     // Gets the page zoom factor as an integer percentage.
     static void getDefaultZoomPercent(GetDefaultZoomPercentCallback callback);
 
     // Sets the page zoom factor from a zoom percentage.
-    static void setDefaultZoomPercent(long percent,
+    static void setDefaultZoomPercent(double percent,

[michaelpg, 2016/10/17 08:46:08]

that is not how percents work... a percent would be 110% not 1.1

this function and the above are now misleadingly named

[Devlin, 2016/10/17 14:51:12]

+1

         optional SetDefaultZoomPercentCallback callback);
   };
 
   interface Events {
     // Fired when a set of prefs has changed.
     //
     // |prefs| The prefs that changed.
     static void onPrefsChanged(PrefObject[] prefs);
   };
 };