[Magnifier - 2] Turn magnifier ON

Flip the flag for turning ON the magnifier attached
to Editor's handles.

Bug: 66657373
Test: bit FrameworksCoreTests:android.widget.TextViewActivityTest
Test: bit CtsWidgetTestCases:android.widget.cts.TextViewTest
Test: manual test that shows the magnifier working
Change-Id: I644c2b834a0c630e5a84a0b948b8667ea988eea6