Do not consolidate data in BMPImageDecoder

Source/platform/image-decoders/FastSharedBufferReader.cpp

Index: Source/platform/image-decoders/FastSharedBufferReader.cpp
diff --git a/Source/platform/image-decoders/FastSharedBufferReader.cpp b/Source/platform/image-decoders/FastSharedBufferReader.cpp
index 3eac7cf1844447158d1351a97bc5d3e01b975128..c4a8107012523bc5da80c7fcd7102378e31d11c3 100644
--- a/Source/platform/image-decoders/FastSharedBufferReader.cpp
+++ b/Source/platform/image-decoders/FastSharedBufferReader.cpp
@@ -41,6 +41,16 @@ FastSharedBufferReader::FastSharedBufferReader(PassRefPtr<SharedBuffer> data)
 {
 }
 
+void FastSharedBufferReader::setData(PassRefPtr<SharedBuffer> data)
+{
+    if (data == m_data)
+        return;
+    m_data = data;
+    m_segment = 0;
+    m_segmentLength = 0;
+    m_dataPosition = 0;
+}
+
 const char* FastSharedBufferReader::getConsecutiveData(size_t dataPosition, size_t length, char* buffer)
 {
     RELEASE_ASSERT(dataPosition + length <= m_data->size());