Add isSafeModeEnabled() API to WindowManagerService

This adds a means of determining when the device is in safe mode,
as required by keyguard to disabled some features.

Change-Id: I31d357e6738c92e1837f9e0263e5f3f4de66315a

Author: Jim Miller

core/java/android/view/IWindowManager.aidl

@@ -254,4 +254,9 @@ interface IWindowManager
      * Gets the infos for all visible windows.
      */
     void getVisibleWindowsForDisplay(int displayId, out List<WindowInfo> outInfos);
+
+    /**
+     * Device is in safe mode.
+     */
+    boolean isSafeModeEnabled();
 }

services/java/com/android/server/wm/WindowManagerService.java

@@ -10347,6 +10347,10 @@ public boolean hasNavigationBar() {
     public void lockNow(Bundle options) {
         mPolicy.lockNow(options);
     }
+    
+    public boolean isSafeModeEnabled() {
+        return mSafeMode;
+    }
 
     void dumpPolicyLocked(PrintWriter pw, String[] args, boolean dumpAll) {
         pw.println("WINDOW MANAGER POLICY STATE (dumpsys window policy)");

tools/layoutlib/bridge/src/android/view/IWindowManagerImpl.java

@@ -446,6 +446,11 @@ public void dismissKeyguard() {
     public void lockNow(Bundle options) {
         // TODO Auto-generated method stub
     }
+    
+    @Override
+    public boolean isSafeModeEnabled() {
+        return false;
+    }
 
     @Override
     public IBinder getFocusedWindowToken() {