Support RGBA fonts and bitmap fonts (and RGBA bitmap fonts)

Quite a few things going on in this commit:

- Enable bitmap strikes by default in Paint objects.

The SkPaint parameter that enables bitmap strikes was not previously
included in DEFAULT_PAINT_FLAGS. This effectively disabled bitmap
fonts. Oops! It's for the best, though, as additional work was needed
in Skia to make bitmap fonts work anyway.

- Complain if TEXTURE_BORDER_SIZE is not 1.

Our glyph cache code does not currently handle any value other than 1
here, including zero. I've added a little C preprocessor check to
prevent future engineers (including especially future-me) from
thinking that they can change this value without updating the related
code.

- Add GL_RGBA support to hwui's FontRenderer and friends

This also happened to involve some refactoring for convenience and
cleanliness.

Bug: 9577689
Change-Id: I0abd1e5a0d6623106247fb6421787e2c2f2ea19c

1 files changed, 1 insertions, 0 deletions

diff --git a/api/current.txt b/api/current.txt
index 8daa592..d134d06 100644
--- a/api/current.txt
+++ b/api/current.txt
@@ -9342,6 +9342,7 @@ package android.graphics {
     field public static final int ANTI_ALIAS_FLAG = 1; // 0x1
     field public static final int DEV_KERN_TEXT_FLAG = 256; // 0x100
     field public static final int DITHER_FLAG = 4; // 0x4
+    field public static final int EMBEDDED_BITMAP_TEXT_FLAG = 1024; // 0x400
     field public static final int FAKE_BOLD_TEXT_FLAG = 32; // 0x20
     field public static final int FILTER_BITMAP_FLAG = 2; // 0x2
     field public static final int HINTING_OFF = 0; // 0x0