Revert "Revert "change computeByteSize to return max_size_t on overflow""

This reverts commit 384f0a7d66.

Bug: skia:
Change-Id: I392ef5c1a5172181caf81ae270befeba6e778241
Reviewed-on: https://skia-review.googlesource.com/57084
Commit-Queue: Mike Reed <reed@google.com>
Commit-Queue: Ben Wagner <bungeman@google.com>
Reviewed-by: Ben Wagner <bungeman@google.com>

include/core/SkImageInfo.h

@@ -317,11 +317,19 @@ public:
     }
 #endif
 
+#ifdef SK_SUPPORT_LEGACY_COMPUTEBYTESIZE_RET_0
     /**
      *  Returns the size (in bytes) of the image buffer that this info needs, given the specified
      *  rowBytes. The rowBytes must be >= this->minRowBytes().
      *  If the calculation overflows, or if the height is 0, this returns 0.
      */
+#else
+    /**
+     *  Returns the size (in bytes) of the image buffer that this info needs, given the specified
+     *  rowBytes. The rowBytes must be >= this->minRowBytes().
+     *  If the calculation overflows this returns SK_MaxSizeT
+     */
+#endif
     size_t computeByteSize(size_t rowBytes) const;
 
     /**
@@ -334,7 +342,11 @@ public:
 
     // Returns true if the result of computeByteSize (or computeMinByteSize) overflowed
     static bool ByteSizeOverflowed(size_t byteSize) {
+#ifdef SK_SUPPORT_LEGACY_COMPUTEBYTESIZE_RET_0
         return 0 == byteSize;
+#else
+        return SK_MaxSizeT == byteSize;
+#endif
     }
 
     bool validRowBytes(size_t rowBytes) const {

include/core/SkTypes.h

@@ -233,6 +233,7 @@ template <typename D, typename S> D SkTo(S s) {
 #define SK_MaxU32   0xFFFFFFFF
 #define SK_MinU32   0
 #define SK_NaN32    ((int) (1U << 31))
+#define SK_MaxSizeT SIZE_MAX
 
 static inline int32_t SkLeftShift(int32_t value, int32_t shift) {
     return (int32_t) ((uint32_t) value << shift);

public.bzl

@@ -656,6 +656,7 @@ DEFINES_ALL = [
     # Required for building dm.
     "GR_TEST_UTILS",
     # Staging flags for API changes
+    "SK_SUPPORT_LEGACY_COMPUTEBYTESIZE_RET_0",
     # Should remove after we update golden images
     "SK_WEBP_ENCODER_USE_DEFAULT_METHOD",
     # Experiment to diagnose image diffs in Google3

src/core/SkImageInfo.cpp

@@ -78,7 +78,11 @@ size_t SkImageInfo::computeByteSize(size_t rowBytes) const {
     SkSafeMath safe;
     size_t bytes = safe.add(safe.mul(fHeight - 1, rowBytes),
                             safe.mul(fWidth, this->bytesPerPixel()));
+#ifdef SK_SUPPORT_LEGACY_COMPUTEBYTESIZE_RET_0
     return safe ? bytes : 0;
+#else
+    return safe ? bytes : SK_MaxSizeT;
+#endif
 }
 
 static bool alpha_type_is_valid(SkAlphaType alphaType) {