Revert of Use the GrCacheable ID to eliminate the need for notifications to GrGpuGL when textures and RTs are… (https://codereview.chromium.org/376703009/)

Reason for revert:
Trying to unblock roll wedged on 64 bit intrinsic call on XP

Original issue's description:
> Use the GrCacheable ID to eliminate the need for notifications to GrGpuGL when textures and RTs are deleted.
>
> Also, rename GrCacheable::getGenerationID() to getInstanceID() since it doesn't behave like other "generation" IDs.
>
> Committed: https://skia.googlesource.com/skia/+/91bdbcdbbdf5cdf0fdb4518a0d30206c964cfdf6

R=jvanverth@google.com, bsalomon@google.com
TBR=bsalomon@google.com, jvanverth@google.com
NOTREECHECKS=true
NOTRY=true

Author: robertphillips@google.com

Review URL: https://codereview.chromium.org/405023003
diff --git a/src/gpu/GrBitmapTextContext.h b/src/gpu/GrBitmapTextContext.h
index c9bb9fd..b9d5ce7 100644
--- a/src/gpu/GrBitmapTextContext.h
+++ b/src/gpu/GrBitmapTextContext.h
@@ -48,7 +48,7 @@
     int32_t                     fMaxVertices;
     GrTexture*                  fCurrTexture;
     SkAutoTUnref<GrEffect>      fCachedEffect;
-    uint64_t                    fEffectTextureInstanceID;
+    uint32_t                    fEffectTextureGenID;
     int                         fCurrVertex;
     SkRect                      fVertexBounds;
 };