Properly scale text

This change does not apply to drawPosText() and drawTextOnPath() yet.

Prior to this change, glyphs were always rasterized based on the
font size specified in the paint. All transforms were then applied
on the resulting texture. This creates rather ugly results when
text is scaled and/or rotated.

With this change, the font renderer will apply the current transform
matrix to the glyph before they are rasterized. This generates much
better looking results.

Change-Id: I0141b6ff18db35e1213e7a3ab9db1ecaf03d7a9c
diff --git a/libs/hwui/Matrix.h b/libs/hwui/Matrix.h
index 46a5597..2fe96bc 100644
--- a/libs/hwui/Matrix.h
+++ b/libs/hwui/Matrix.h
@@ -152,6 +152,8 @@
 
     void dump() const;
 
+    static const Matrix4& identity();
+
 private:
     mutable uint32_t mType;