[WebGL] Return meaningful information in WebGL context creation error message.

[WebGL] Return meaningful information in WebGL context creation error message.
For example, vendor, renderer, driver version, etc.This
way a developer can gather data on what platforms the app
fails to run. This needs changes on both blink and chromium.

Below steps are followed to implement this

1. Add basic headers in blink.
2. Add the necessary apis in chromium.
3. Start using this in WebglRenderingContxt.cpp.

This patch represents step-3 in this process.

BUG=412440
Committed: https://src.chromium.org/viewvc/blink?view=rev&revision=184830

[sivag, 2014-11-01 18:03:42]

siva.gunturi@samsung.com changed reviewers:
+ kbr@chromium.org

[sivag, 2014-11-01 18:17:42]

@kbr, ptal

[Ken Russell (switch to Gerrit), 2014-11-04 00:37:49]

LGTM with minor comments addressed.

https://codereview.chromium.org/695563003/diff/1/Source/core/html/canvas/WebG...
File Source/core/html/canvas/WebGLRenderingContext.cpp (right):

https://codereview.chromium.org/695563003/diff/1/Source/core/html/canvas/WebG...
Source/core/html/canvas/WebGLRenderingContext.cpp:91:
statusMessage.append("VendorInfo= ");
Combine these two constant strings. Add space between "for" and "VendorInfo".

https://codereview.chromium.org/695563003/diff/1/Source/core/html/canvas/WebG...
Source/core/html/canvas/WebGLRenderingContext.cpp:94:
statusMessage.append("RendererInfo= ");
Combine the adjacent constant strings here and below.

[sivag, 2014-11-04 12:33:32]

https://codereview.chromium.org/695563003/diff/1/Source/core/html/canvas/WebG...
File Source/core/html/canvas/WebGLRenderingContext.cpp (right):

https://codereview.chromium.org/695563003/diff/1/Source/core/html/canvas/WebG...
Source/core/html/canvas/WebGLRenderingContext.cpp:91:
statusMessage.append("VendorInfo= ");
On 2014/11/04 00:37:49, Ken Russell wrote:
> Combine these two constant strings. Add space between "for" and "VendorInfo".

Done.

https://codereview.chromium.org/695563003/diff/1/Source/core/html/canvas/WebG...
Source/core/html/canvas/WebGLRenderingContext.cpp:94:
statusMessage.append("RendererInfo= ");
On 2014/11/04 00:37:49, Ken Russell wrote:
> Combine the adjacent constant strings here and below.

Done.

[sivag, 2014-11-04 12:33:39]

The CQ bit was checked by siva.gunturi@samsung.com

[commit-bot: I haz the power, 2014-11-04 12:33:53]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/695563003/40001

[commit-bot: I haz the power, 2014-11-04 16:17:01]

Committed patchset #3 (id:40001) as 184830