Pass EXCLUDE_FROM_RECENTS when starting secure camera.

Camera started from the secure lock screen does not
show all the pictures in the camera roll. If users
launch camera from recent apps, they may enter secure
camera mode accidentally. Pass EXCLUDE_FROM_RECENTS
flag to prevent this.

bug:7053266
Change-Id: I0ad526d919dac02f358b25493777d7d73da6987f

Author: Wu-cheng Li

policy/src/com/android/internal/policy/impl/keyguard/KeyguardSelectorView.java

@@ -131,7 +131,9 @@ public KeyguardSelectorView(Context context) {
     protected void launchCamera() {
         if (mLockPatternUtils.isSecure()) {
             // Launch the secure version of the camera
-            launchActivity(new Intent(MediaStore.INTENT_ACTION_STILL_IMAGE_CAMERA_SECURE), true);
+            Intent intent = new Intent(MediaStore.INTENT_ACTION_STILL_IMAGE_CAMERA_SECURE);
+            intent.addFlags(Intent.FLAG_ACTIVITY_EXCLUDE_FROM_RECENTS);
+            launchActivity(intent, true);
         } else {
             // Launch the normal camera
             launchActivity(new Intent(MediaStore.INTENT_ACTION_STILL_IMAGE_CAMERA), false);
@@ -230,7 +232,7 @@ public void setLockPatternUtils(LockPatternUtils utils) {
      * See {@link WindowManager#FLAG_SHOW_WHEN_LOCKED}
      */
     private void launchActivity(final Intent intent, boolean showsWhileLocked) {
-        intent.setFlags(
+        intent.addFlags(
                 Intent.FLAG_ACTIVITY_NEW_TASK
                 | Intent.FLAG_ACTIVITY_SINGLE_TOP
                 | Intent.FLAG_ACTIVITY_CLEAR_TOP);