--- a/gfx/layers/LayersLogging.cpp
+++ b/gfx/layers/LayersLogging.cpp
@@ -222,36 +222,16 @@ AppendToString(std::stringstream& aStrea
     aStream << nsPrintfCString(
       "[ %g %g; %g %g; %g %g; ]",
       m._11, m._12, m._21, m._22, m._31, m._32).get();
   }
   aStream << sfx;
 }
 
 void
-AppendToString(std::stringstream& aStream, const Matrix4x4& m,
-               const char* pfx, const char* sfx)
-{
-  if (m.Is2D()) {
-    Matrix matrix = m.As2D();
-    AppendToString(aStream, matrix, pfx, sfx);
-    return;
-  }
-
-  aStream << pfx;
-  aStream << nsPrintfCString(
-    "[ %g %g %g %g; %g %g %g %g; %g %g %g %g; %g %g %g %g; ]",
-    m._11, m._12, m._13, m._14,
-    m._21, m._22, m._23, m._24,
-    m._31, m._32, m._33, m._34,
-    m._41, m._42, m._43, m._44).get();
-  aStream << sfx;
-}
-
-void
 AppendToString(std::stringstream& aStream, const Matrix5x4& m,
                const char* pfx, const char* sfx)
 {
   aStream << pfx;
   aStream << nsPrintfCString(
     "[ %g %g %g %g; %g %g %g %g; %g %g %g %g; %g %g %g %g; %g %g %g %g]",
     m._11, m._12, m._13, m._14,
     m._21, m._22, m._23, m._24,

--- a/gfx/layers/LayersLogging.h
+++ b/gfx/layers/LayersLogging.h
@@ -2,17 +2,17 @@
  * This Source Code Form is subject to the terms of the Mozilla Public
  * License, v. 2.0. If a copy of the MPL was not distributed with this
  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
 
 #ifndef GFX_LAYERSLOGGING_H
 #define GFX_LAYERSLOGGING_H
 
 #include "FrameMetrics.h"               // for FrameMetrics, etc
-#include "mozilla/gfx/MatrixFwd.h"      // for Matrix4x4
+#include "mozilla/gfx/Matrix.h"         // for Matrix4x4
 #include "mozilla/gfx/Point.h"          // for IntSize, etc
 #include "mozilla/gfx/Types.h"          // for Filter, SurfaceFormat
 #include "mozilla/layers/CompositorTypes.h"  // for TextureFlags
 #include "nsAString.h"
 #include "nsPrintfCString.h"            // for nsPrintfCString
 #include "nsRegion.h"                   // for nsRegion, nsIntRegion
 #include "nscore.h"                     // for nsACString, etc
 
@@ -180,19 +180,36 @@ AppendToString(std::stringstream& aStrea
   aStream.precision(oldPrecision);
   aStream << sfx;
 }
 
 void
 AppendToString(std::stringstream& aStream, const mozilla::gfx::Matrix& m,
                const char* pfx="", const char* sfx="");
 
+template<class SourceUnits, class TargetUnits>
 void
-AppendToString(std::stringstream& aStream, const mozilla::gfx::Matrix4x4& m,
-               const char* pfx="", const char* sfx="");
+AppendToString(std::stringstream& aStream, const mozilla::gfx::Matrix4x4Typed<SourceUnits, TargetUnits>& m,
+               const char* pfx="", const char* sfx="")
+{
+  if (m.Is2D()) {
+    mozilla::gfx::Matrix matrix = m.As2D();
+    AppendToString(aStream, matrix, pfx, sfx);
+    return;
+  }
+
+  aStream << pfx;
+  aStream << nsPrintfCString(
+    "[ %g %g %g %g; %g %g %g %g; %g %g %g %g; %g %g %g %g; ]",
+    m._11, m._12, m._13, m._14,
+    m._21, m._22, m._23, m._24,
+    m._31, m._32, m._33, m._34,
+    m._41, m._42, m._43, m._44).get();
+  aStream << sfx;
+}
 
 void
 AppendToString(std::stringstream& aStream, const mozilla::gfx::Matrix5x4& m,
                const char* pfx="", const char* sfx="");
 
 void
 AppendToString(std::stringstream& aStream, const mozilla::gfx::Filter filter,
                const char* pfx="", const char* sfx="");