Revert of Move npot resizing out of GrContext and simplify GrContext texture function...

Revert of Move npot resizing out of GrContext and simplify GrContext texture functions. (patchset #9 id:160001 of https://codereview.chromium.org/882223003/)

Reason for revert:
webGL conformance failures:

WebglConformance.conformance_textures_tex_image_and_sub_image_2d_with_video
WebglConformance.conformance_textures_texture_npot_video

https://codereview.chromium.org/892773003/
http://build.chromium.org/p/tryserver.chromium.mac/builders/mac_chromium_rel_ng/builds/29272

Original issue's description:
> Move npot resizing out of GrContext and simplify GrContext texture functions.
>
> Committed: https://skia.googlesource.com/skia/+/8a8100349105c8c6de39fcb34e47679da7a67f54

TBR=robertphillips@google.com,bsalomon@google.com
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true

Review URL: https://codereview.chromium.org/868233005