Bug 1140830 - Don't try to use a null JSONObject in SiteIdentity.update() r=rnewman

This patch avoids a crash in ART on HTC One M8 devices, where a (deliberate?) NPE was used for init.

mobile/android/base/SiteIdentity.java

@@ -119,22 +119,26 @@ public class SiteIdentity {
     }
 
     public SiteIdentity() {
-        resetIdentityData();
-
-        mMixedMode = MixedMode.UNKNOWN;
-        mTrackingMode = TrackingMode.UNKNOWN;
+        reset();
     }
 
-    private void resetIdentityData() {
+    public void reset() {
         mSecurityMode = SecurityMode.UNKNOWN;
         mHost = null;
         mOwner = null;
         mSupplemental = null;
         mVerifier = null;
         mEncrypted = null;
+        mMixedMode = MixedMode.UNKNOWN;
+        mTrackingMode = TrackingMode.UNKNOWN;
     }
 
     void update(JSONObject identityData) {
+        if (identityData == null) {
+            reset();
+            return;
+        }
+
         try {
             JSONObject mode = identityData.getJSONObject("mode");
 
@@ -153,7 +157,7 @@ public class SiteIdentity {
             try {
                 mSecurityMode = SecurityMode.fromString(mode.getString("identity"));
             } catch (Exception e) {
-                resetIdentityData();
+                reset();
                 return;
             }
 
@@ -164,10 +168,10 @@ public class SiteIdentity {
                 mVerifier = identityData.getString("verifier");
                 mEncrypted = identityData.getString("encrypted");
             } catch (Exception e) {
-                resetIdentityData();
+                reset();
             }
         } catch (Exception e) {
-            resetIdentityData();
+            reset();
             mMixedMode = MixedMode.UNKNOWN;
             mTrackingMode = TrackingMode.UNKNOWN;
         }

mobile/android/base/Tab.java

@@ -612,7 +612,7 @@ public class Tab {
 
         setHasFeeds(false);
         setHasOpenSearch(false);
-        updateIdentityData(null);
+        mSiteIdentity.reset();
         setZoomConstraints(new ZoomConstraints(true));
         setHasTouchListeners(false);
         setBackgroundColor(DEFAULT_BACKGROUND_COLOR);
@@ -629,7 +629,7 @@ public class Tab {
     void handleDocumentStart(boolean restoring, String url) {
         setLoadProgress(LOAD_PROGRESS_START);
         setState((!restoring && shouldShowProgress(url)) ? STATE_LOADING : STATE_SUCCESS);
-        updateIdentityData(null);
+        mSiteIdentity.reset();
     }
 
     void handleDocumentStop(boolean success) {