Add notification to power save mode

Add small notification when mode is toggled and also disable web refiner
and edge navigation.

Change-Id: I166897c0e396b53884e05dac8189f049f34851f7
diff --git a/src/com/android/browser/BaseUi.java b/src/com/android/browser/BaseUi.java
index 3682d69..3a05724 100644
--- a/src/com/android/browser/BaseUi.java
+++ b/src/com/android/browser/BaseUi.java
@@ -446,7 +446,7 @@
     }
 
     public void refreshEdgeSwipeController(View container) {
-        if (BrowserCommandLine.hasSwitch("ui-low-power-mode")) {
+        if (isUiLowPowerMode()) {
             return;
         }
 
@@ -696,6 +696,11 @@
         return false;
     }
 
+    public static boolean isUiLowPowerMode() {
+        return BrowserCommandLine.hasSwitch("ui-low-power-mode") ||
+            BrowserSettings.getInstance().isPowerSaveModeEnabled();
+    }
+
     // -------------------------------------------------------------------------
 
     protected void updateNavigationState(Tab tab) {