Convert GrAppliedClip interface to builder style

GrAppliedClip was about at its limit for how many "make" functions it
could have. Window rectangles would push it over the edge. This change
makes it so GrDrawTarget supplies the original draw bounds to the
constructor, and then GrClip adds the various required clipping
techniques.

BUG=skia:
GOLD_TRYBOT_URL= https://gold.skia.org/search?issue=2246113002

Review-Url: https://codereview.chromium.org/2246113002
diff --git a/src/gpu/GrReducedClip.cpp b/src/gpu/GrReducedClip.cpp
index f7bac4a..132936c 100644
--- a/src/gpu/GrReducedClip.cpp
+++ b/src/gpu/GrReducedClip.cpp
@@ -343,9 +343,7 @@
     // generation id. When we make early returns, we do not know what was the generation
     // id that lead to the state. Make a conservative guess.
     fGenID = stack.getTopmostGenID();
-
-    // TODO: instead devise a way of telling the caller to disregard some or all of the clip bounds.
-    fIBounds = GrClip::GetPixelIBounds(queryBounds);
+    fHasIBounds = false;
 
     if (stack.isWideOpen()) {
         fInitialState = InitialState::kAllIn;
@@ -372,6 +370,7 @@
             // The clip is a non-aa rect. This is the one spot where we can actually implement the
             // clip (using fIBounds) rather than just telling the caller what it should be.
             stackBounds.round(&fIBounds);
+            fHasIBounds = true;
             fInitialState = fIBounds.isEmpty() ? InitialState::kAllOut : InitialState::kAllIn;
             return;
         }
@@ -380,8 +379,11 @@
             return;
         }
 
-        SkAssertResult(fIBounds.intersect(GrClip::GetPixelIBounds(stackBounds)));
+        SkRect tightBounds;
+        SkAssertResult(tightBounds.intersect(stackBounds, queryBounds));
+        fIBounds = GrClip::GetPixelIBounds(tightBounds);
         SkASSERT(!fIBounds.isEmpty()); // Empty should have been blocked by IsOutsideClip above.
+        fHasIBounds = true;
 
         // Implement the clip with an AA rect element.
         fElements.addToHead(stackBounds, SkRegion::kReplace_Op, true/*doAA*/);
@@ -396,10 +398,11 @@
         // Tighten the query by introducing a new clip at the stack's pixel boundaries. (This new
         // clip will be enforced by the scissor through fIBounds.)
         SkAssertResult(tighterQuery.intersect(GrClip::GetPixelBounds(stackBounds)));
-        fIBounds = GrClip::GetPixelIBounds(tighterQuery);
     }
 
+    fIBounds = GrClip::GetPixelIBounds(tighterQuery);
     SkASSERT(!fIBounds.isEmpty()); // Empty should have been blocked by IsOutsideClip above.
+    fHasIBounds = true;
 
     // Now that we have determined the bounds to use and filtered out the trivial cases, call the
     // helper that actually walks the stack.