Share code in various SkGPipeCanvas::drawBitmap_ calls.

Share code in various SkGPipeCanvas::drawBitmap_ calls.

Also implement SkGPipeCanvas::drawBitmapMatrix, and
create a GM to make sure it works properly.

Use a flag instead of writing a bool for determining whether
drawBitmap_ has a paint and whether drawBitmapRect has a source
rectangle.

BUG=
TEST=drawbitmapmatrix GM

Committed: https://code.google.com/p/skia/source/detail?r=4828

[reed1, 2012-07-26 21:20:03]

can we make the gm picture prettier?

https://codereview.appspot.com/6450053/diff/1/src/pipe/SkGPipePriv.h
File src/pipe/SkGPipePriv.h (right):

https://codereview.appspot.com/6450053/diff/1/src/pipe/SkGPipePriv.h#newcode142
src/pipe/SkGPipePriv.h:142: // which is used for all drawBitmap calls, so
include it here.
_HasSrcRect_ ...

https://codereview.appspot.com/6450053/diff/1/src/pipe/SkGPipeRead.cpp
File src/pipe/SkGPipeRead.cpp (right):

https://codereview.appspot.com/6450053/diff/1/src/pipe/SkGPipeRead.cpp#newcod...
src/pipe/SkGPipeRead.cpp:439: unsigned flags = DrawOp_unpackFlags(op32);
Need to use 

bool foo = SkToBool(int-expression)

to ensure we convert to a bool w/o warning

[Leon, 2012-07-26 22:06:15]

https://codereview.appspot.com/6450053/diff/1/src/pipe/SkGPipePriv.h
File src/pipe/SkGPipePriv.h (right):

https://codereview.appspot.com/6450053/diff/1/src/pipe/SkGPipePriv.h#newcode142
src/pipe/SkGPipePriv.h:142: // which is used for all drawBitmap calls, so
include it here.
On 2012/07/26 21:20:03, reed1 wrote:
> _HasSrcRect_ ...

Done.

https://codereview.appspot.com/6450053/diff/1/src/pipe/SkGPipeRead.cpp
File src/pipe/SkGPipeRead.cpp (right):

https://codereview.appspot.com/6450053/diff/1/src/pipe/SkGPipeRead.cpp#newcod...
src/pipe/SkGPipeRead.cpp:439: unsigned flags = DrawOp_unpackFlags(op32);
On 2012/07/26 21:20:03, reed1 wrote:
> Need to use 
> 
> bool foo = SkToBool(int-expression)
> 
> to ensure we convert to a bool w/o warning

Done.

[Leon, 2012-07-30 13:24:37]

New patch uploaded addressing comments.

[reed1, 2012-07-30 14:15:54]

lgtm