Revert of add isRect() check to AAClip, to detect if a soft-clip is really just an irect (https://codereview.chromium.org/445233006/)

Reason for revert:
new code asserts on some pictures

Original issue's description:
> add isRect() check to AAClip, to detect if a soft-clip is really just an irect
>
> BUG=skia:
>
> Committed: https://skia.googlesource.com/skia/+/592cb8d552556b1e922887d506d00b64bc5d0547

R=bsalomon@google.com, humper@google.com
TBR=bsalomon@google.com, humper@google.com
NOTREECHECKS=true
NOTRY=true
BUG=skia:

Author: reed@google.com

Review URL: https://codereview.chromium.org/452533002

4 files changed, 3 insertions, 47 deletions

diff --git a/src/core/SkAAClip.cpp b/src/core/SkAAClip.cpp
index 54a6dcd795..14152f8317 100644
--- a/src/core/SkAAClip.cpp
+++ b/src/core/SkAAClip.cpp
@@ -684,35 +684,6 @@ bool SkAAClip::setRect(const SkIRect& bounds) {
 #endif
 }
 
-bool SkAAClip::isRect() const {
-    if (this->isEmpty()) {
-        return false;
-    }
-
-    const RunHead* head = fRunHead;
-    if (head->fRowCount != 1) {
-        return false;
-    }
-    const YOffset* yoff = head->yoffsets();
-    if (yoff->fY != fBounds.fBottom - 1) {
-        return false;
-    }
-    SkASSERT(0 == yoff->fOffset);
-
-    const uint8_t* row = head->data();
-    int width = fBounds.width();
-    do {
-        if (row[1] != 0xFF) {
-            return false;
-        }
-        int n = row[0];
-        SkASSERT(n <= width);
-        width -= n;
-        row += 2;
-    } while (width > 0);
-    return true;
-}
-
 bool SkAAClip::setRect(const SkRect& r, bool doAA) {
     if (r.isEmpty()) {
         return this->setEmpty();
diff --git a/src/core/SkAAClip.h b/src/core/SkAAClip.h
index c36a3e98ce..f2cde62dbc 100644
--- a/src/core/SkAAClip.h
+++ b/src/core/SkAAClip.h
@@ -29,10 +29,6 @@ public:
     bool isEmpty() const { return NULL == fRunHead; }
     const SkIRect& getBounds() const { return fBounds; }
 
-    // Returns true iff the clip is not empty, and is just a hard-edged rect (no partial alpha).
-    // If true, getBounds() can be used in place of this clip.
-    bool isRect() const;
-
     bool setEmpty();
     bool setRect(const SkIRect&);
     bool setRect(const SkRect&, bool doAA = true);
diff --git a/src/core/SkRasterClip.cpp b/src/core/SkRasterClip.cpp
index d1615a3445..664211f64f 100644
--- a/src/core/SkRasterClip.cpp
+++ b/src/core/SkRasterClip.cpp
@@ -222,10 +222,7 @@ void SkRasterClip::convertToAA() {
     SkASSERT(fIsBW);
     fAA.setRegion(fBW);
     fIsBW = false;
-    
-    // since we are being explicitly asked to convert-to-aa, we pass false so we don't "optimize"
-    // ourselves back to BW.
-    (void)this->updateCacheAndReturnNonEmpty(false);
+    (void)this->updateCacheAndReturnNonEmpty();
 }
 
 #ifdef SK_DEBUG
diff --git a/src/core/SkRasterClip.h b/src/core/SkRasterClip.h
index 29a925f2a2..0c2723314c 100644
--- a/src/core/SkRasterClip.h
+++ b/src/core/SkRasterClip.h
@@ -89,19 +89,11 @@ private:
     }
 
     bool computeIsRect() const {
-        return fIsBW ? fBW.isRect() : fAA.isRect();
+        return fIsBW ? fBW.isRect() : false;
     }
 
-    bool updateCacheAndReturnNonEmpty(bool detectAARect = true) {
+    bool updateCacheAndReturnNonEmpty() {
         fIsEmpty = this->computeIsEmpty();
-
-        // detect that our computed AA is really just a (hard-edged) rect
-        if (detectAARect && !fIsEmpty && !fIsBW && fAA.isRect()) {
-            fBW.setRect(fAA.getBounds());
-            fAA.setEmpty(); // don't need this guy anymore
-            fIsBW = true;
-        }
-
         fIsRect = this->computeIsRect();
         return !fIsEmpty;
     }