Moving test related to Dragging to their own class from TaplTestsLauncher3

Renaming the following test names:
 - testDragAppIconToWorkspaceCell to testDragAppIconToMultipleWorkspaceCells
 - testDragShortcutToMultipleWoCells to testDragShortcutToMultipleWorkspaceCells

Bug: 298234173
Test: atest OopTaplDragTest
Change-Id: I16707e0a882164c7a5acec6a4197bd0bea8514a7

tests/src/com/android/launcher3/ui/AbstractLauncherUiTest.java

@@ -123,6 +123,10 @@ public abstract class AbstractLauncherUiTest {
                 }, DEFAULT_UI_TIMEOUT, launcher);
     }
 
+    public static String getAppPackageName() {
+        return getInstrumentation().getContext().getPackageName();
+    }
+
     private static String getActivityLeakErrorMessage(LauncherInstrumentation launcher) {
         sActivityLeakReported = true;
         return "Activity leak detector has found leaked activities, "