Revert "Detect Chrome either by renderer or version strings."

This reverts commit be4eed2ef7.

Reason for revert: <INSERT REASONING HERE>

Original change's description:
> Detect Chrome either by renderer or version strings.
> 
> We currently detect Chrome by GL_RENDERER. In anticipation of changes in Chrome to no longer override the renderer string we now also check the version string.
> 
> Change-Id: Ice4ac3ae8ced5ac3d8fd2099300f0a3285f9c197
> Reviewed-on: https://skia-review.googlesource.com/9807
> Reviewed-by: Greg Daniel <egdaniel@google.com>
> Commit-Queue: Brian Salomon <bsalomon@google.com>
> 

TBR=egdaniel@google.com,bsalomon@google.com,reviews@skia.org
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true

Change-Id: I0100ce266ca9bf7b71a752495e509e67ff323870
Reviewed-on: https://skia-review.googlesource.com/9811
Reviewed-by: Brian Salomon <bsalomon@google.com>
Commit-Queue: Brian Salomon <bsalomon@google.com>

src/gpu/gl/GrGLUtil.cpp

@@ -111,8 +111,7 @@ void GrGLGetDriverInfo(GrGLStandard standard,
         versionString = "";
     }
 
-    if (0 == strcmp(rendererString, "Chromium") ||
-        2 == sscanf(versionString, "OpenGL ES %d.%d Chromium", &major, &minor)) {
+    if (0 == strcmp(rendererString, "Chromium")) {
         *outDriver = kChromium_GrGLDriver;
         return;
     }