--- a/gfx/thebes/gfxAndroidPlatform.cpp
+++ b/gfx/thebes/gfxAndroidPlatform.cpp
@@ -241,17 +241,17 @@ gfxAndroidPlatform::CreatePlatformFontLi
     if (NS_SUCCEEDED(list->InitFontList())) {
         return list;
     }
     gfxPlatformFontList::Shutdown();
     return nullptr;
 }
 
 bool
-gfxAndroidPlatform::IsFontFormatSupported(nsIURI *aFontURI, uint32_t aFormatFlags)
+gfxAndroidPlatform::IsFontFormatSupported(uint32_t aFormatFlags)
 {
     // check for strange format flags
     NS_ASSERTION(!(aFormatFlags & gfxUserFontSet::FLAG_FORMAT_NOT_USED),
                  "strange font format hint set");
 
     // accept supported formats
     if (aFormatFlags & gfxUserFontSet::FLAG_FORMATS_COMMON) {
         return true;

--- a/gfx/thebes/gfxAndroidPlatform.h
+++ b/gfx/thebes/gfxAndroidPlatform.h
@@ -35,17 +35,17 @@ public:
     
     already_AddRefed<mozilla::gfx::ScaledFont>
       GetScaledFontForFont(mozilla::gfx::DrawTarget* aTarget, gfxFont *aFont) override;
 
     // to support IPC font list (sharing between chrome and content)
     void GetSystemFontList(InfallibleTArray<FontListEntry>* retValue);
 
     // platform implementations of font functions
-    virtual bool IsFontFormatSupported(nsIURI *aFontURI, uint32_t aFormatFlags) override;
+    virtual bool IsFontFormatSupported(uint32_t aFormatFlags) override;
     virtual gfxPlatformFontList* CreatePlatformFontList() override;
 
     virtual void GetCommonFallbackFonts(uint32_t aCh, uint32_t aNextCh,
                                         Script aRunScript,
                                         nsTArray<const char*>& aFontList) override;
 
     gfxFontGroup*
     CreateFontGroup(const mozilla::FontFamilyList& aFontFamilyList,

--- a/gfx/thebes/gfxPlatform.h
+++ b/gfx/thebes/gfxPlatform.h
@@ -467,17 +467,17 @@ public:
 
     /**
      * Whether to use the SIL Graphite rendering engine
      * (for fonts that include Graphite tables)
      */
     bool UseGraphiteShaping();
 
     // check whether format is supported on a platform or not (if unclear, returns true)
-    virtual bool IsFontFormatSupported(nsIURI *aFontURI, uint32_t aFormatFlags) { return false; }
+    virtual bool IsFontFormatSupported(uint32_t aFormatFlags) { return false; }
 
     virtual bool DidRenderingDeviceReset(DeviceResetReason* aResetReason = nullptr) { return false; }
 
     // returns a list of commonly used fonts for a given character
     // these are *possible* matches, no cmap-checking is done at this level
     virtual void GetCommonFallbackFonts(uint32_t /*aCh*/, uint32_t /*aNextCh*/,
                                         Script /*aRunScript*/,
                                         nsTArray<const char*>& /*aFontList*/)

--- a/gfx/thebes/gfxPlatformGtk.cpp
+++ b/gfx/thebes/gfxPlatformGtk.cpp
@@ -306,17 +306,17 @@ gfxPlatformGtk::MakePlatformFont(const n
 
 FT_Library
 gfxPlatformGtk::GetFTLibrary()
 {
     return gfxFcPlatformFontList::GetFTLibrary();
 }
 
 bool
-gfxPlatformGtk::IsFontFormatSupported(nsIURI *aFontURI, uint32_t aFormatFlags)
+gfxPlatformGtk::IsFontFormatSupported(uint32_t aFormatFlags)
 {
     // check for strange format flags
     NS_ASSERTION(!(aFormatFlags & gfxUserFontSet::FLAG_FORMAT_NOT_USED),
                  "strange font format hint set");
 
     // accept supported formats
     // Pango doesn't apply features from AAT TrueType extensions.
     // Assume that if this is the only SFNT format specified,

--- a/gfx/thebes/gfxPlatformGtk.h
+++ b/gfx/thebes/gfxPlatformGtk.h
@@ -82,18 +82,17 @@ public:
                                            uint8_t aStyle,
                                            const uint8_t* aFontData,
                                            uint32_t aLength) override;
 
     /**
      * Check whether format is supported on a platform or not (if unclear,
      * returns true).
      */
-    virtual bool IsFontFormatSupported(nsIURI *aFontURI,
-                                         uint32_t aFormatFlags) override;
+    virtual bool IsFontFormatSupported(uint32_t aFormatFlags) override;
 
     /**
      * Calls XFlush if xrender is enabled.
      */
     virtual void FlushContentDrawing() override;
 
     FT_Library GetFTLibrary() override;
 

--- a/gfx/thebes/gfxPlatformMac.cpp
+++ b/gfx/thebes/gfxPlatformMac.cpp
@@ -147,17 +147,17 @@ gfxPlatformMac::CreateFontGroup(const Fo
                                 gfxUserFontSet *aUserFontSet,
                                 gfxFloat aDevToCssSize)
 {
     return new gfxFontGroup(aFontFamilyList, aStyle, aTextPerf,
                             aUserFontSet, aDevToCssSize);
 }
 
 bool
-gfxPlatformMac::IsFontFormatSupported(nsIURI *aFontURI, uint32_t aFormatFlags)
+gfxPlatformMac::IsFontFormatSupported(uint32_t aFormatFlags)
 {
     // check for strange format flags
     NS_ASSERTION(!(aFormatFlags & gfxUserFontSet::FLAG_FORMAT_NOT_USED),
                  "strange font format hint set");
 
     // accept supported formats
     if (aFormatFlags & (gfxUserFontSet::FLAG_FORMATS_COMMON |
                         gfxUserFontSet::FLAG_FORMAT_TRUETYPE_AAT)) {

--- a/gfx/thebes/gfxPlatformMac.h
+++ b/gfx/thebes/gfxPlatformMac.h
@@ -41,17 +41,17 @@ public:
                     gfxFloat aDevToCssSize) override;
 
     virtual gfxPlatformFontList* CreatePlatformFontList() override;
 
     void
     GetSystemFontFamilyList(InfallibleTArray<mozilla::dom::FontFamilyListEntry>*
                             aFontFamilies) override;
 
-    bool IsFontFormatSupported(nsIURI *aFontURI, uint32_t aFormatFlags) override;
+    bool IsFontFormatSupported(uint32_t aFormatFlags) override;
 
     virtual void GetCommonFallbackFonts(uint32_t aCh, uint32_t aNextCh,
                                         Script aRunScript,
                                         nsTArray<const char*>& aFontList) override;
 
     // lookup the system font for a particular system font type and set
     // the name and style characteristics
     static void

--- a/gfx/thebes/gfxUserFontSet.cpp
+++ b/gfx/thebes/gfxUserFontSet.cpp
@@ -527,17 +527,16 @@ gfxUserFontEntry::DoLoadNextSrc(bool aFo
                      NS_ConvertUTF16toUTF8(currSrc.mLocalName).get(),
                      NS_ConvertUTF16toUTF8(mFamilyName).get()));
             }
         }
 
         // src url ==> start the load process
         else if (currSrc.mSourceType == gfxFontFaceSrc::eSourceType_URL) {
             if (gfxPlatform::GetPlatform()->IsFontFormatSupported(
-                    currSrc.mURI->get(),
                     currSrc.mFormatFlags)) {
 
                 if (ServoStyleSet* set = ServoStyleSet::Current()) {
                     set->AppendTask(PostTraversalTask::LoadFontEntry(this));
                     SetLoadState(STATUS_LOAD_PENDING);
                     return;
                 }
 

--- a/gfx/thebes/gfxWindowsPlatform.cpp
+++ b/gfx/thebes/gfxWindowsPlatform.cpp
@@ -876,17 +876,17 @@ gfxWindowsPlatform::CreateFontGroup(cons
                                     gfxUserFontSet *aUserFontSet,
                                     gfxFloat aDevToCssSize)
 {
     return new gfxFontGroup(aFontFamilyList, aStyle, aTextPerf,
                             aUserFontSet, aDevToCssSize);
 }
 
 bool
-gfxWindowsPlatform::IsFontFormatSupported(nsIURI *aFontURI, uint32_t aFormatFlags)
+gfxWindowsPlatform::IsFontFormatSupported(uint32_t aFormatFlags)
 {
     // check for strange format flags
     NS_ASSERTION(!(aFormatFlags & gfxUserFontSet::FLAG_FORMAT_NOT_USED),
                  "strange font format hint set");
 
     // accept supported formats
     if (aFormatFlags & gfxUserFontSet::FLAG_FORMATS_COMMON) {
         return true;

--- a/gfx/thebes/gfxWindowsPlatform.h
+++ b/gfx/thebes/gfxWindowsPlatform.h
@@ -169,17 +169,17 @@ public:
                     gfxUserFontSet *aUserFontSet,
                     gfxFloat aDevToCssSize) override;
 
     virtual bool CanUseHardwareVideoDecoding() override;
 
     /**
      * Check whether format is supported on a platform or not (if unclear, returns true)
      */
-    virtual bool IsFontFormatSupported(nsIURI *aFontURI, uint32_t aFormatFlags) override;
+    virtual bool IsFontFormatSupported(uint32_t aFormatFlags) override;
 
     virtual void CompositorUpdated() override;
 
     bool DidRenderingDeviceReset(DeviceResetReason* aResetReason = nullptr) override;
     void SchedulePaintIfDeviceReset() override;
 
     mozilla::gfx::BackendType GetContentBackendFor(mozilla::layers::LayersBackend aLayers) override;