Fix out-of-memory crashes related to ArrayBuffer allocation

third_party/WebKit/Source/core/fileapi/FileReader.cpp

Index: third_party/WebKit/Source/core/fileapi/FileReader.cpp
diff --git a/third_party/WebKit/Source/core/fileapi/FileReader.cpp b/third_party/WebKit/Source/core/fileapi/FileReader.cpp
index c983c37d5ef4e9fbfab04291bcd09e8694ee46c6..cbb664b3be518c7ab55d0d99133a40f77808e233 100644
--- a/third_party/WebKit/Source/core/fileapi/FileReader.cpp
+++ b/third_party/WebKit/Source/core/fileapi/FileReader.cpp
@@ -370,10 +370,19 @@ void FileReader::result(StringOrArrayBuffer& resultAttribute) const
     if (!m_loader || m_error)
         return;
 
-    if (m_readType == FileReaderLoader::ReadAsArrayBuffer)
-        resultAttribute.setArrayBuffer(m_loader->arrayBufferResult());
-    else
+    if (m_readType == FileReaderLoader::ReadAsArrayBuffer) {
+        // FIXME(crbug.com/536816):
+        // In on-going work for crbug.com/536816 the code was left in this state
+        // to avoid changing pre-existing behavior, but we may want to revisit
+        // this code to determine the proper course of action for cases where
+        // arrayBufferResultOrNull() returns a nullptr, presumably due to a
+        // memory allocation failure. Would it be aprropriate to throw a
+        // RangeError DOM exception from here? Should we cancel the setting
+        // of resultAttribute instead of setting it to null?
+        resultAttribute.setArrayBuffer(m_loader->arrayBufferResultOrNull());
+    } else {
         resultAttribute.setString(m_loader->stringResult());
+    }
 }
 
 void FileReader::terminate()