Make GrClipMaskManager stateless and push GrPipelineBuilder construction downstack

src/gpu/GrUserStencilSettings.h

 /*
  * Copyright 2016 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 
 #ifndef GrUserStencilSettings_DEFINED
 #define GrUserStencilSettings_DEFINED
@@ skipping 170 matching lines @@
     // This struct can only be constructed with static initializers.
     GrUserStencilSettings() = delete;
     GrUserStencilSettings(const GrUserStencilSettings&) = delete;
 
     const uint16_t   fFrontFlags[2]; // frontFlagsForDraw = fFrontFlags[hasStencilClip].
     const Face       fFront;
     const uint16_t   fBackFlags[2]; // backFlagsForDraw = fBackFlags[hasStencilClip].
     const Face       fBack;
 
     static const GrUserStencilSettings& kUnused;
+
+    bool isUnused() const { return this == &kUnused; }
 };
 
 template<GrUserStencilTest Test, GrUserStencilOp PassOp, GrUserStencilOp FailOp>
 struct GrUserStencilSettings::Attrs {
     // Ensure an op that only modifies user bits isn't paired with one that modifies clip bits.
     GR_STATIC_ASSERT(GrUserStencilOp::kKeep == PassOp || GrUserStencilOp::kKeep == FailOp ||
                      (PassOp <= kLastUserOnlyStencilOp) == (FailOp <= kLastUserOnlyStencilOp));
     // Ensure an op that only modifies clip bits isn't paired with one that modifies clip and user.
     GR_STATIC_ASSERT(GrUserStencilOp::kKeep == PassOp || GrUserStencilOp::kKeep == FailOp ||
                      (PassOp <= kLastClipOnlyStencilOp) == (FailOp <= kLastClipOnlyStencilOp));
@@ skipping 27 matching lines @@
     }
     constexpr static uint16_t EffectiveWriteMask(uint16_t writeMask) {
         // We don't modify the mask differently when hasStencilClip=false because either the entire
         // face gets disabled in that case (e.g. Test=kAlwaysIfInClip, PassOp=kKeep), or else the
         // effective mask stays the same either way.
         return DoesNotModifyStencil(true) ? 0 : writeMask;
     }
 };
 
 #endif