Do not crash when log called on a background thread

[pchmielowski]

When DebugOverlay.with(this).log("Message"); is called on a background thread, CalledFromWrongThreadException occur with the following stack trace:

android.view.ViewRootImpl$CalledFromWrongThreadException: Only the original thread that created a view hierarchy can touch its views.
                                                                                            at android.view.ViewRootImpl.checkThread(ViewRootImpl.java:7286)
                                                                                            at android.view.ViewRootImpl.requestLayout(ViewRootImpl.java:1155)
                                                                                            at android.view.View.requestLayout(View.java:21926)
                                                                                            at android.view.View.requestLayout(View.java:21926)
                                                                                            at android.widget.AbsListView.requestLayout(AbsListView.java:1998)
                                                                                            at android.widget.AdapterView$AdapterDataSetObserver.onChanged(AdapterView.java:848)
                                                                                            at android.widget.AbsListView$AdapterDataSetObserver.onChanged(AbsListView.java:6414)
                                                                                            at android.database.DataSetObservable.notifyChanged(DataSetObservable.java:37)
                                                                                            at android.widget.BaseAdapter.notifyDataSetChanged(BaseAdapter.java:50)
                                                                                            at com.hannesdorfmann.debugoverlay.DebugOverlayView.addMessage(DebugOverlayView.java:90)
                                                                                            at com.hannesdorfmann.debugoverlay.DebugOverlayService.logMsg(DebugOverlayService.java:45)
                                                                                            at com.hannesdorfmann.debugoverlay.DebugOverlay$MessageDispatcher.dispatch(DebugOverlay.java:118)
                                                                                            at com.hannesdorfmann.debugoverlay.DebugOverlay$MessageDispatcher.enqueueMessage(DebugOverlay.java:101)
                                                                                            at com.hannesdorfmann.debugoverlay.DebugOverlay.log(DebugOverlay.java:54)

To reproduce it, please checkout 898d23f commit from this pull request, set Foregroung thread switch to false and press fab more than once.

Commit cf66434 fixes this issue by invoking view.addMessage(msg) on the UI thread.

[pchmielowski]

@sockeqwe Any chances to merge this PR?

[sockeqwe]

Sorry, @pchmielowski I somehow overlooked your PR. I have released a new version 0.4.0 with a fix for this problem (but different technical solution, therefore closed this PR).