Fix crash logging exception

Bug 3099377. The rest of the code is full of lines like this:
  Log.e(TAG, e.getMessage(), e);
I tested code like that and when getMessage() is null it
will log (but not crash):
E/MessageListAdapter( 2210): null
E/MessageListAdapter( 2210): com.google.android.mms.MmsException
E/MessageListAdapter( 2210): 	at com.android.mms.ui.MessageListAdapter.newView(MessageListAdapter.java:255)
E/MessageListAdapter( 2210): 	at android.widget.CursorAdapter.getView(CursorAdapter.java:182)

Change-Id: I728e20cc5f0d8e986d67d2964d04682645a550d4
diff --git a/src/com/android/mms/ui/MessageListAdapter.java b/src/com/android/mms/ui/MessageListAdapter.java
index 222df63..bc2bea5 100644
--- a/src/com/android/mms/ui/MessageListAdapter.java
+++ b/src/com/android/mms/ui/MessageListAdapter.java
@@ -262,7 +262,7 @@
                 item = new MessageItem(mContext, type, c, mColumnsMap, mHighlight);
                 mMessageItemCache.put(getKey(item.mType, item.mMsgId), item);
             } catch (MmsException e) {
-                Log.e(TAG, e.getMessage());
+                Log.e(TAG, "getCachedMessageItem: ", e);
             }
         }
         return item;