Fix fuzzer-found deserialization bugs

src/core/SkPath.cpp

 /*
  * Copyright 2006 The Android Open Source Project
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #include "SkBuffer.h"
 #include "SkCubicClipper.h"
 #include "SkErrorInternals.h"
@@ skipping 1891 matching lines @@
         return 0;
     }
 
     unsigned version = packed & 0xFF;
 
     fConvexity = (packed >> kConvexity_SerializationShift) & 0xFF;
     fFillType = (packed >> kFillType_SerializationShift) & 0xFF;
     uint8_t dir = (packed >> kDirection_SerializationShift) & 0x3;
     fIsVolatile = (packed >> kIsVolatile_SerializationShift) & 0x1;
     SkPathRef* pathRef = SkPathRef::CreateFromBuffer(&buffer);
+    if (!pathRef) {
+        return 0;
+    }
+
+    fPathRef.reset(pathRef);
+    SkDEBUGCODE(this->validate();)
+    buffer.skipToAlign4();
 
     // compatibility check
     if (version < kPathPrivFirstDirection_Version) {
         switch (dir) {  // old values
             case 0:
                 fFirstDirection = SkPathPriv::kUnknown_FirstDirection;
                 break;
             case 1:
                 fFirstDirection = SkPathPriv::kCW_FirstDirection;
                 break;
             case 2:
                 fFirstDirection = SkPathPriv::kCCW_FirstDirection;
                 break;
             default:
                 SkASSERT(false);
         }
     } else {
         fFirstDirection = dir;
     }
 
-    size_t sizeRead = 0;
-    if (buffer.isValid()) {
-        fPathRef.reset(pathRef);
-        SkDEBUGCODE(this->validate();)
-        buffer.skipToAlign4();
-        sizeRead = buffer.pos();
-    } else if (pathRef) {
-        // If the buffer is not valid, pathRef should be nullptr
-        sk_throw();
-    }
-    return sizeRead;
+    return buffer.pos();
 }
 
 ///////////////////////////////////////////////////////////////////////////////
 
 #include "SkStringUtils.h"
 #include "SkStream.h"
 
 static void append_params(SkString* str, const char label[], const SkPoint pts[],
                           int count, SkScalarAsStringType strType, SkScalar conicWeight = -1) {
     str->append(label);
@@ skipping 1134 matching lines @@
         }
     } while (!done);
     return SkToBool(tangents.count()) ^ isInverse;
 }
 
 int SkPath::ConvertConicToQuads(const SkPoint& p0, const SkPoint& p1, const SkPoint& p2,
                                 SkScalar w, SkPoint pts[], int pow2) {
     const SkConic conic(p0, p1, p2, w);
     return conic.chopIntoQuadsPOW2(pts, pow2);
 }