Revert "Revert of https://codereview.chromium.org/113823003/"

This reverts commit 68b4b32066ea0ba9dbb5d326a836f8a54297b7aa.

BUG=

Review URL: https://codereview.chromium.org/122293002

git-svn-id: http://skia.googlecode.com/svn/trunk@12842 2bbb7eff-a529-9590-31e7-b0007b416f81

2 files changed, 5 insertions, 10 deletions

diff --git a/src/images/SkImageDecoder_libpng.cpp b/src/images/SkImageDecoder_libpng.cpp
index 02ba6af90a..3cc41e3f59 100644
--- a/src/images/SkImageDecoder_libpng.cpp
+++ b/src/images/SkImageDecoder_libpng.cpp
@@ -607,13 +607,9 @@ bool SkPNGImageDecoder::getBitmapConfig(png_structp png_ptr, png_infop info_ptr,
 
     // sanity check for size
     {
-        Sk64 size;
-        size.setMul(origWidth, origHeight);
-        if (size.isNeg() || !size.is32()) {
-            return false;
-        }
+        int64_t size = sk_64_mul(origWidth, origHeight);
         // now check that if we are 4-bytes per pixel, we also don't overflow
-        if (size.get32() > (0x7FFFFFFF >> 2)) {
+        if (size < 0 || size > (0x7FFFFFFF >> 2)) {
             return false;
         }
     }
diff --git a/src/images/SkImageDecoder_libwebp.cpp b/src/images/SkImageDecoder_libwebp.cpp
index 4a5951020e..05925d03a2 100644
--- a/src/images/SkImageDecoder_libwebp.cpp
+++ b/src/images/SkImageDecoder_libwebp.cpp
@@ -80,13 +80,12 @@ static bool webp_parse_header(SkStream* stream, int* width, int* height, int* al
 
     // sanity check for image size that's about to be decoded.
     {
-        Sk64 size;
-        size.setMul(*width, *height);
-        if (size.isNeg() || !size.is32()) {
+        int64_t size = sk_64_mul(*width, *height);
+        if (!sk_64_isS32(size)) {
             return false;
         }
         // now check that if we are 4-bytes per pixel, we also don't overflow
-        if (size.get32() > (0x7FFFFFFF >> 2)) {
+        if (sk_64_asS32(size) > (0x7FFFFFFF >> 2)) {
             return false;
         }
     }