Fix ANGLE build

Fix ANGLE build

Removed this in r5889.
Committed: https://code.google.com/p/skia/source/detail?r=5904

[bsalomon, 2012-10-11 18:54:08]

On 2012/10/11 18:45:22, EricB wrote:

Here is an alterna-fix which doesn't require making views depend on seeing
include/gpu: https://codereview.appspot.com/6659044

[epoger, 2012-10-11 18:59:50]

On 2012/10/11 18:54:08, bsalomon wrote:
> On 2012/10/11 18:45:22, EricB wrote:
> 
> Here is an alterna-fix which doesn't require making views depend on seeing
> include/gpu: https://codereview.appspot.com/6659044

I prefer the alterna-fix...

[bsalomon, 2012-10-11 19:08:12]

On 2012/10/11 18:59:50, epoger wrote:
> On 2012/10/11 18:54:08, bsalomon wrote:
> > On 2012/10/11 18:45:22, EricB wrote:
> > 
> > Here is an alterna-fix which doesn't require making views depend on seeing
> > include/gpu: https://codereview.appspot.com/6659044
> 
> I prefer the alterna-fix...

Making the alterna-fix confused me... somehow we are including both the system
GL.h and ANGLE's gl2.h which have many colliding #defines, typedefs, functions,
etc. Yet making glFoo() calls seemed to work for both the native GL and the
ANGLE GLES2. I don't get how it worked before or after my change. But I feel
like my change adds to the confusion by making glFoo() calls that are supposed
to go to ANGLE in addition to the existing glFoo() calls that are supposed to go
to the native GL.

[bsalomon, 2012-10-11 19:10:30]

lgtm

[bsalomon, 2012-10-11 19:29:25]

Ok, I get why the existing code worked. The GrGLInterface doesn't actually use
glFoo(). Instead it uses LoadLibrary()/GetProcAddress() to get a pointer to
ANGLE's implementation of glFoo().

So Eric's change is definitely better than mine. My change was making native GL
calls in place of ANGLE calls. I just didn't notice any visual errors when
running SampleApp.