BMP-in-ICO should respect alpha in Windows V3 32bpp RGB bitmaps.

Source/platform/image-decoders/bmp/BMPImageReader.h

Index: Source/platform/image-decoders/bmp/BMPImageReader.h
diff --git a/Source/platform/image-decoders/bmp/BMPImageReader.h b/Source/platform/image-decoders/bmp/BMPImageReader.h
index 1c440eecc9b71738cfd64091f63084cd9cbc6a2f..664dab6170fee9430115f99d8623139fd4eece1d 100644
--- a/Source/platform/image-decoders/bmp/BMPImageReader.h
+++ b/Source/platform/image-decoders/bmp/BMPImageReader.h
@@ -68,7 +68,7 @@ public:
     // |startOffset| points to the start of the BMP within the file.
     // |buffer| points at an empty ImageFrame that we'll initialize and
     // fill with decoded data.
-    BMPImageReader(ImageDecoder* parent, size_t decodedAndHeaderOffset, size_t imgDataOffset, bool usesAndMask);
+    BMPImageReader(ImageDecoder* parent, size_t decodedAndHeaderOffset, size_t imgDataOffset, bool m_isInICO);

[Stephen White, 2014/05/07 22:38:55]

Spurious m_.

[Peter Kasting, 2014/05/07 22:41:29]

Darn!  Good catch.  Will fix.

 
     void setBuffer(ImageFrame* buffer) { m_buffer = buffer; }
     void setData(SharedBuffer* data) { m_data = data; }
@@ -94,11 +94,6 @@ private:
         HUFFMAN1D,  // Stored in file as 3
         RLE24,      // Stored in file as 4
     };
-    enum AndMaskState {
-        None,
-        NotYetDecoded,
-        Decoding,
-    };
     enum ProcessingResult {
         Success,
         Failure,
@@ -343,11 +338,15 @@ private:
     bool m_seenNonZeroAlphaPixel;
     bool m_seenZeroAlphaPixel;
 
+    // BMPs-in-ICOs have a few differences from standalone BMPs, so we need to
+    // know if we're in an ICO container.
+    bool m_isInICO;
+
     // ICOs store a 1bpp "mask" immediately after the main bitmap image data
     // (and, confusingly, add its height to the biHeight value in the info
-    // header, thus doubling it).  This variable tracks whether we have such
-    // a mask and if we've started decoding it yet.
-    AndMaskState m_andMaskState;
+    // header, thus doubling it). If |m_isInICO| is true, this variable tracks
+    // whether we've begun decoding this mask yet.
+    bool m_decodingAndMask;
 };
 
 } // namespace WebCore