Improve error reporting: Extract original message when showing "Java exception messages" consistently. Improve error handling in deprecated OneDrive API stub and avoid crash by no-longer throwing in Main-thread methods.

src/keepass2android-app/search/SearchResults.cs

@@ -142,7 +142,7 @@ namespace keepass2android.search
                 }
             } catch (Exception e) {
 				Kp2aLog.LogUnexpectedError(e);
-				App.Kp2a.ShowMessage(this,e.Message,  MessageSeverity.Error);
+				App.Kp2a.ShowMessage(this, Util.GetErrorMessage(e),  MessageSeverity.Error);
 				Finish();
 				return;
 			}