Remove some unnecessary #includes of SkImageFilter.h

R=robertphillips@google.com
TBR=reed@google.com
BUG=skia:
GOLD_TRYBOT_URL= https://gold.skia.org/search2?unt=true&query=source_type%3Dgm&master=false&issue=1907283002

Review URL: https://codereview.chromium.org/1907283002

include/gpu/GrTextureProvider.h

@@ -10,7 +10,6 @@
 
 #include "GrTexture.h"
 #include "GrTypes.h"
-#include "SkImageFilter.h"
 
 class GrSingleOwner;
 

src/core/SkSpecialImage.h

@@ -12,9 +12,6 @@
 #include "SkRefCnt.h"
 #include "SkSurfaceProps.h"
 
-// remove this when internal_getProxy goes away (see skbug.com/4965)
-#include "SkImageFilter.h"
-
 #include "SkImageInfo.h" // for SkAlphaType
 
 class GrContext;

src/image/SkImage_Gpu.cpp

@@ -16,7 +16,6 @@
 #include "SkGpuDevice.h"
 #include "SkGrPixelRef.h"
 #include "SkGrPriv.h"
-#include "SkImageFilter.h"
 #include "SkImage_Gpu.h"
 #include "SkPixelRef.h"