Remove GrProgramDesc's need for the GrGpu

Although not strictly necessary, being able to compute the program key w/o needing access to the Gpu will give us more flexibility.

Bug: skia:9455
Change-Id: I0cd76d79a3008b69be18636be370e7aaa531bc65
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/247686
Commit-Queue: Robert Phillips <robertphillips@google.com>
Reviewed-by: Greg Daniel <egdaniel@google.com>
diff --git a/src/gpu/GrPrimitiveProcessor.cpp b/src/gpu/GrPrimitiveProcessor.cpp
index 5ca399a..87b6f3f 100644
--- a/src/gpu/GrPrimitiveProcessor.cpp
+++ b/src/gpu/GrPrimitiveProcessor.cpp
@@ -55,20 +55,17 @@
 
 GrPrimitiveProcessor::TextureSampler::TextureSampler(const GrSamplerState& samplerState,
                                                      const GrBackendFormat& backendFormat,
-                                                     const GrSwizzle& swizzle,
-                                                     uint32_t extraSamplerKey) {
-    this->reset(samplerState, backendFormat, swizzle, extraSamplerKey);
+                                                     const GrSwizzle& swizzle) {
+    this->reset(samplerState, backendFormat, swizzle);
 }
 
 void GrPrimitiveProcessor::TextureSampler::reset(const GrSamplerState& samplerState,
                                                  const GrBackendFormat& backendFormat,
-                                                 const GrSwizzle& swizzle,
-                                                 uint32_t extraSamplerKey) {
+                                                 const GrSwizzle& swizzle) {
     fSamplerState = samplerState;
     fSamplerState.setFilterMode(clamp_filter(backendFormat.textureType(), samplerState.filter()));
     fBackendFormat = backendFormat;
     fSwizzle = swizzle;
-    fExtraSamplerKey = extraSamplerKey;
     fIsInitialized = true;
 }