Reland "Update FragmentProcessor TextureSampler to hold an GrSurfaceProxyView."

This reverts commit c5c024791bb7a587223b807e00ffba4a3eb5fdb7.

Reason for revert: Doh

Original change's description:
> Revert "Update FragmentProcessor TextureSampler to hold an GrSurfaceProxyView."
> 
> This reverts commit acf5929ae0addc5188117142fd3fb39828baa8d5.
> 
> Reason for revert: May be blocking Chrome roll
> Original change's description:
> > Update FragmentProcessor TextureSampler to hold an GrSurfaceProxyView.
> > 
> > In future CLs I will update the Ops that create the TextureSamplers to pass
> > the GrSurfaceProxyView in.
> > 
> > Bug: skia:9556
> > Change-Id: I550dab64974d32e4c3047188063efa2d0832328e
> > Reviewed-on: https://skia-review.googlesource.com/c/skia/+/259164
> > Commit-Queue: Greg Daniel <egdaniel@google.com>
> > Reviewed-by: Michael Ludwig <michaelludwig@google.com>
> 
> TBR=egdaniel@google.com,michaelludwig@google.com
> 
> Change-Id: Ic804a52c5c6d16a13a9cc2d85bb959f305134177
> No-Presubmit: true
> No-Tree-Checks: true
> No-Try: true
> Bug: skia:9556
> Reviewed-on: https://skia-review.googlesource.com/c/skia/+/259433
> Reviewed-by: Robert Phillips <robertphillips@google.com>
> Commit-Queue: Robert Phillips <robertphillips@google.com>

TBR=egdaniel@google.com,robertphillips@google.com,michaelludwig@google.com

Change-Id: If2af5b5b323858e59c0c8db3b75477d74d78abfd
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Bug: skia:9556
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/259434
Reviewed-by: Robert Phillips <robertphillips@google.com>
Commit-Queue: Robert Phillips <robertphillips@google.com>
diff --git a/src/gpu/effects/generated/GrMagnifierEffect.cpp b/src/gpu/effects/generated/GrMagnifierEffect.cpp
index 5a29834..a6522b5 100644
--- a/src/gpu/effects/generated/GrMagnifierEffect.cpp
+++ b/src/gpu/effects/generated/GrMagnifierEffect.cpp
@@ -85,8 +85,8 @@
             pdman.set1f(xInvInsetVar, (_outer.xInvInset));
             pdman.set1f(yInvInsetVar, (_outer.yInvInset));
         }
-        GrSurfaceProxy& srcProxy = *_outer.textureSampler(0).proxy();
-        GrTexture& src = *srcProxy.peekTexture();
+        const GrSurfaceProxyView& srcView = _outer.textureSampler(0).view();
+        GrTexture& src = *srcView.proxy()->peekTexture();
         (void)src;
         auto bounds = _outer.bounds;
         (void)bounds;
@@ -110,7 +110,7 @@
 
         {
             SkScalar y = srcRect.y() * invH;
-            if (srcProxy.origin() != kTopLeft_GrSurfaceOrigin) {
+            if (srcView.origin() != kTopLeft_GrSurfaceOrigin) {
                 y = 1.0f - (srcRect.height() / bounds.height()) - y;
             }
 
@@ -120,7 +120,7 @@
         {
             SkScalar y = bounds.y() * invH;
             SkScalar hSign = 1.f;
-            if (srcProxy.origin() != kTopLeft_GrSurfaceOrigin) {
+            if (srcView.origin() != kTopLeft_GrSurfaceOrigin) {
                 y = 1.0f - bounds.y() * invH;
                 hSign = -1.f;
             }