Bug 775042 - Clear downloads when clearing history. r=mfinkle

mobile/android/base/resources/values/arrays.xml

@@ -68,7 +68,7 @@
         <item>true</item>
     </string-array>
     <string-array name="pref_private_data_keys">
-        <item>private.data.history</item>
+        <item>private.data.history_downloads</item>
         <item>private.data.formdata</item>
         <item>private.data.cookies</item>
         <item>private.data.cache</item>

mobile/android/chrome/content/browser.js

@@ -799,7 +799,14 @@ var BrowserApp = {
         continue;
 
       try {
-        sanitizer.clearItem(key);
+        switch (key) {
+          case "history_downloads":
+            sanitizer.clearItem("history");
+            sanitizer.clearItem("downloads");
+            break;
+          default:
+            sanitizer.clearItem(key);
+        }
       } catch (e) {
         dump("sanitize error: " + e);
         success = false;