--- a/gfx/2d/NativeFontResourceDWrite.cpp
+++ b/gfx/2d/NativeFontResourceDWrite.cpp
@@ -7,17 +7,16 @@
 #include "NativeFontResourceDWrite.h"
 #include "UnscaledFontDWrite.h"
 
 #include <unordered_map>
 
 #include "Logging.h"
 #include "mozilla/RefPtr.h"
 #include "mozilla/StaticMutex.h"
-#include "nsTArray.h"
 
 namespace mozilla {
 namespace gfx {
 
 static StaticMutex sFontFileStreamsMutex;
 static uint64_t sNextFontFileKey = 0;
 static std::unordered_map<uint64_t, IDWriteFontFileStream*> sFontFileStreams;
 
@@ -80,27 +79,25 @@ public:
 
 private:
   static IDWriteFontFileLoader* mInstance;
 };
 
 class DWriteFontFileStream final : public IDWriteFontFileStream
 {
 public:
-  DWriteFontFileStream(uint64_t aFontFileKey);
-
   /**
     * Used by the FontFileLoader to create a new font stream,
     * this font stream is created from data in memory. The memory
     * passed may be released after object creation, it will be
     * copied internally.
     *
     * @param aData Font data
     */
-  bool Initialize(uint8_t *aData, uint32_t aSize);
+  DWriteFontFileStream(uint8_t *aData, uint32_t aSize, uint64_t aFontFileKey);
 
   // IUnknown interface
   IFACEMETHOD(QueryInterface)(IID const& iid, OUT void** ppObject)
   {
     if (iid == __uuidof(IDWriteFontFileStream)) {
       *ppObject = static_cast<IDWriteFontFileStream*>(this);
       return S_OK;
     } else if (iid == __uuidof(IUnknown)) {
@@ -133,17 +130,17 @@ public:
 
   virtual void STDMETHODCALLTYPE ReleaseFileFragment(void* fragmentContext);
 
   virtual HRESULT STDMETHODCALLTYPE GetFileSize(OUT UINT64* fileSize);
 
   virtual HRESULT STDMETHODCALLTYPE GetLastWriteTime(OUT UINT64* lastWriteTime);
 
 private:
-  nsTArray<uint8_t> mData;
+  std::vector<uint8_t> mData;
   Atomic<uint32_t> mRefCnt;
   uint64_t mFontFileKey;
 
   ~DWriteFontFileStream();
 };
 
 IDWriteFontFileLoader* DWriteFontFileLoader::mInstance = nullptr;
 
@@ -164,59 +161,52 @@ DWriteFontFileLoader::CreateStreamFromKe
     return E_FAIL;
   }
 
   found->second->AddRef();
   *fontFileStream = found->second;
   return S_OK;
 }
 
-DWriteFontFileStream::DWriteFontFileStream(uint64_t aFontFileKey)
+DWriteFontFileStream::DWriteFontFileStream(uint8_t *aData, uint32_t aSize,
+                                           uint64_t aFontFileKey)
   : mRefCnt(0)
   , mFontFileKey(aFontFileKey)
 {
+  mData.resize(aSize);
+  memcpy(&mData.front(), aData, aSize);
 }
 
 DWriteFontFileStream::~DWriteFontFileStream()
 {
   StaticMutexAutoLock lock(sFontFileStreamsMutex);
   sFontFileStreams.erase(mFontFileKey);
 }
 
-bool
-DWriteFontFileStream::Initialize(uint8_t *aData, uint32_t aSize)
-{
-  if (!mData.SetLength(aSize, fallible)) {
-    return false;
-  }
-  memcpy(mData.Elements(), aData, aSize);
-  return true;
-}
-
 HRESULT STDMETHODCALLTYPE
 DWriteFontFileStream::GetFileSize(UINT64 *fileSize)
 {
-  *fileSize = mData.Length();
+  *fileSize = mData.size();
   return S_OK;
 }
 
 HRESULT STDMETHODCALLTYPE
 DWriteFontFileStream::GetLastWriteTime(UINT64 *lastWriteTime)
 {
   return E_NOTIMPL;
 }
 
 HRESULT STDMETHODCALLTYPE
 DWriteFontFileStream::ReadFileFragment(const void **fragmentStart,
                                        UINT64 fileOffset,
                                        UINT64 fragmentSize,
                                        void **fragmentContext)
 {
   // We are required to do bounds checking.
-  if (fileOffset + fragmentSize > mData.Length()) {
+  if (fileOffset + fragmentSize > mData.size()) {
     return E_FAIL;
   }
 
   // truncate the 64 bit fileOffset to size_t sized index into mData
   size_t index = static_cast<size_t>(fileOffset);
 
   // We should be alive for the duration of this.
   *fragmentStart = &mData[index];
@@ -237,22 +227,18 @@ NativeFontResourceDWrite::Create(uint8_t
   RefPtr<IDWriteFactory> factory = Factory::GetDWriteFactory();
   if (!factory) {
     gfxWarning() << "Failed to get DWrite Factory.";
     return nullptr;
   }
 
   sFontFileStreamsMutex.Lock();
   uint64_t fontFileKey = sNextFontFileKey++;
-  RefPtr<DWriteFontFileStream> ffsRef = new DWriteFontFileStream(fontFileKey);
-  if (!ffsRef->Initialize(aFontData, aDataLength)) {
-    sFontFileStreamsMutex.Unlock();
-    gfxWarning() << "Failed to create DWriteFontFileStream.";
-    return nullptr;
-  }
+  RefPtr<IDWriteFontFileStream> ffsRef =
+    new DWriteFontFileStream(aFontData, aDataLength, fontFileKey);
   sFontFileStreams[fontFileKey] = ffsRef;
   sFontFileStreamsMutex.Unlock();
 
   RefPtr<IDWriteFontFile> fontFile;
   HRESULT hr =
     factory->CreateCustomFontFileReference(&fontFileKey, sizeof(fontFileKey),
                                            DWriteFontFileLoader::Instance(),
                                            getter_AddRefs(fontFile));

--- a/gfx/2d/NativeFontResourceFontconfig.cpp
+++ b/gfx/2d/NativeFontResourceFontconfig.cpp
@@ -27,20 +27,17 @@ NativeFontResourceFontconfig::~NativeFon
 }
 
 already_AddRefed<NativeFontResourceFontconfig>
 NativeFontResourceFontconfig::Create(uint8_t *aFontData, uint32_t aDataLength, FT_Library aFTLibrary)
 {
   if (!aFontData || !aDataLength) {
     return nullptr;
   }
-  UniquePtr<uint8_t[]> fontData(new (fallible) uint8_t[aDataLength]);
-  if (!fontData) {
-    return nullptr;
-  }
+  UniquePtr<uint8_t[]> fontData(new uint8_t[aDataLength]);
   memcpy(fontData.get(), aFontData, aDataLength);
 
   FT_Face face = Factory::NewFTFaceFromData(aFTLibrary, fontData.get(), aDataLength, 0);
   if (!face) {
     return nullptr;
   }
   if (FT_Select_Charmap(face, FT_ENCODING_UNICODE) != FT_Err_Ok) {
     Factory::ReleaseFTFace(face);