Bold StyleSpan further for auto-bold

StyleSpan with Typeface.BOLD will only bold if the text doesn't already
have a BOLD style. But auto-bolded text needs to be further bolded.
If the Typeface style is BOLD, bold more for auto-bold.
(The fake bold works for Typefaces with weight < 700)

Test: manual - settings page, example StyleSpans,
atest StyleSpanTest TextViewTests
Bug: 175177807

Change-Id: Iec7db7eadd18ed6a2efc6ee39b49c1d6cb15d870