Add GrContext::resetGLTextureBindings().

This function binds texture ID 0 to any texture unit/target combo that
Skia has modified.

Bug: chromium:926017
Change-Id: I3ac8f8050c863232886102886e60d3b91a5380c9
Reviewed-on: https://skia-review.googlesource.com/c/190663
Commit-Queue: Brian Salomon <bsalomon@google.com>
Reviewed-by: Brian Osman <brianosman@google.com>
diff --git a/tools/gpu/gl/GLTestContext.cpp b/tools/gpu/gl/GLTestContext.cpp
index e11f1b0..2e12b47 100644
--- a/tools/gpu/gl/GLTestContext.cpp
+++ b/tools/gpu/gl/GLTestContext.cpp
@@ -314,9 +314,9 @@
     }
 }
 
-GrGLint GLTestContext::createTextureRectangle(int width, int height, GrGLenum internalFormat,
-                                          GrGLenum externalFormat, GrGLenum externalType,
-                                          GrGLvoid* data) {
+GrGLuint GLTestContext::createTextureRectangle(int width, int height, GrGLenum internalFormat,
+                                               GrGLenum externalFormat, GrGLenum externalType,
+                                               GrGLvoid* data) {
     // Should match GrGLCaps check for fRectangleTextureSupport.
     if (kGL_GrGLStandard != fGL->fStandard ||
         (GrGLGetVersion(fGL.get()) < GR_GL_VER(3, 1) &&