Make multipart/x-mixed-replace parser more robust

third_party/WebKit/Source/core/fetch/ImageResourceTest.cpp

Index: third_party/WebKit/Source/core/fetch/ImageResourceTest.cpp
diff --git a/third_party/WebKit/Source/core/fetch/ImageResourceTest.cpp b/third_party/WebKit/Source/core/fetch/ImageResourceTest.cpp
index 236650a15ea211a2162aad68ab1ae2ab26156ccd..cd4c1595a93e7bb9aaea120749fa22b6bfece9f3 100644
--- a/third_party/WebKit/Source/core/fetch/ImageResourceTest.cpp
+++ b/third_party/WebKit/Source/core/fetch/ImageResourceTest.cpp
@@ -123,11 +123,15 @@ TEST(ImageResourceTest, MultipartImage)
     // The first bytes arrive. The data buffer is created, but no image is created.
     cachedImage->appendData(secondPart, strlen(secondPart));
     ASSERT_TRUE(cachedImage->resourceBuffer());
-    ASSERT_EQ(cachedImage->resourceBuffer()->size(), strlen(secondPart));
     ASSERT_FALSE(cachedImage->hasImage());
     ASSERT_EQ(client.imageChangedCount(), 0);
     ASSERT_FALSE(client.notifyFinishedCalled());
 
+    const char thirdPart[] = "--boundary";
+    cachedImage->appendData(thirdPart, strlen(thirdPart));
+    ASSERT_TRUE(cachedImage->resourceBuffer());
+    ASSERT_EQ(cachedImage->resourceBuffer()->size(), strlen(secondPart) - 1);
+
     // This part finishes. The image is created, callbacks are sent, and the data buffer is cleared.
     cachedImage->finish();
     ASSERT_FALSE(cachedImage->resourceBuffer());