diff -r 000000000000 -r 6474c204b198 gfx/layers/LayersLogging.cpp
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/gfx/layers/LayersLogging.cpp	Wed Dec 31 06:09:35 2014 +0100
@@ -0,0 +1,229 @@
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*-
+ * vim: sw=2 ts=8 et :
+ */
+/* 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/. */
+
+#include "LayersLogging.h"
+#include <stdint.h>                     // for uint8_t
+#include "gfx3DMatrix.h"                // for gfx3DMatrix
+#include "gfxColor.h"                   // for gfxRGBA
+#include "mozilla/gfx/Matrix.h"         // for Matrix4x4, Matrix
+#include "nsDebug.h"                    // for NS_ERROR
+#include "nsPoint.h"                    // for nsIntPoint
+#include "nsRect.h"                     // for nsIntRect
+#include "nsSize.h"                     // for nsIntSize
+
+using namespace mozilla::gfx;
+
+namespace mozilla {
+namespace layers {
+
+nsACString&
+AppendToString(nsACString& s, const void* p,
+               const char* pfx, const char* sfx)
+{
+  s += pfx;
+  s += nsPrintfCString("%p", p);
+  return s += sfx;
+}
+
+nsACString&
+AppendToString(nsACString& s, const GraphicsFilter& f,
+               const char* pfx, const char* sfx)
+{
+  s += pfx;
+  switch (f) {
+  case GraphicsFilter::FILTER_FAST:      s += "fast"; break;
+  case GraphicsFilter::FILTER_GOOD:      s += "good"; break;
+  case GraphicsFilter::FILTER_BEST:      s += "best"; break;
+  case GraphicsFilter::FILTER_NEAREST:   s += "nearest"; break;
+  case GraphicsFilter::FILTER_BILINEAR:  s += "bilinear"; break;
+  case GraphicsFilter::FILTER_GAUSSIAN:  s += "gaussian"; break;
+  default:
+    NS_ERROR("unknown filter type");
+    s += "???";
+  }
+  return s += sfx;
+}
+
+nsACString&
+AppendToString(nsACString& s, FrameMetrics::ViewID n,
+               const char* pfx, const char* sfx)
+{
+  s += pfx;
+  s.AppendInt(n);
+  return s += sfx;
+}
+
+nsACString&
+AppendToString(nsACString& s, const gfxRGBA& c,
+               const char* pfx, const char* sfx)
+{
+  s += pfx;
+  s += nsPrintfCString(
+    "rgba(%d, %d, %d, %g)",
+    uint8_t(c.r*255.0), uint8_t(c.g*255.0), uint8_t(c.b*255.0), c.a);
+  return s += sfx;
+}
+
+nsACString&
+AppendToString(nsACString& s, const nsIntPoint& p,
+               const char* pfx, const char* sfx)
+{
+  s += pfx;
+  s += nsPrintfCString("(x=%d, y=%d)", p.x, p.y);
+  return s += sfx;
+}
+
+nsACString&
+AppendToString(nsACString& s, const nsIntRect& r,
+               const char* pfx, const char* sfx)
+{
+  s += pfx;
+  s += nsPrintfCString(
+    "(x=%d, y=%d, w=%d, h=%d)",
+    r.x, r.y, r.width, r.height);
+  return s += sfx;
+}
+
+nsACString&
+AppendToString(nsACString& s, const nsIntRegion& r,
+               const char* pfx, const char* sfx)
+{
+  s += pfx;
+
+  nsIntRegionRectIterator it(r);
+  s += "< ";
+  while (const nsIntRect* sr = it.Next())
+    AppendToString(s, *sr) += "; ";
+  s += ">";
+
+  return s += sfx;
+}
+
+nsACString&
+AppendToString(nsACString& s, const nsIntSize& sz,
+               const char* pfx, const char* sfx)
+{
+  s += pfx;
+  s += nsPrintfCString("(w=%d, h=%d)", sz.width, sz.height);
+  return s += sfx;
+}
+
+nsACString&
+AppendToString(nsACString& s, const FrameMetrics& m,
+               const char* pfx, const char* sfx)
+{
+  s += pfx;
+  AppendToString(s, m.mViewport, "{ viewport=");
+  AppendToString(s, m.GetScrollOffset(), " viewportScroll=");
+  AppendToString(s, m.mDisplayPort, " displayport=");
+  AppendToString(s, m.mScrollableRect, " scrollableRect=");
+  AppendToString(s, m.GetScrollId(), " scrollId=", " }");
+  return s += sfx;
+}
+
+nsACString&
+AppendToString(nsACString& s, const IntSize& size,
+               const char* pfx, const char* sfx)
+{
+  s += pfx;
+  s += nsPrintfCString(
+    "(width=%d, height=%d)",
+    size.width, size.height);
+  return s += sfx;
+}
+
+nsACString&
+AppendToString(nsACString& s, const Matrix4x4& m,
+               const char* pfx, const char* sfx)
+{
+  s += pfx;
+  if (m.Is2D()) {
+    Matrix matrix = m.As2D();
+    if (matrix.IsIdentity()) {
+      s += "[ I ]";
+      return s += sfx;
+    }
+    s += nsPrintfCString(
+      "[ %g %g; %g %g; %g %g; ]",
+      matrix._11, matrix._12, matrix._21, matrix._22, matrix._31, matrix._32);
+  } else {
+    s += 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);
+  }
+  return s += sfx;
+}
+
+nsACString&
+AppendToString(nsACString& s, const Filter filter,
+               const char* pfx, const char* sfx)
+{
+  s += pfx;
+
+  switch (filter) {
+    case Filter::GOOD: s += "Filter::GOOD"; break;
+    case Filter::LINEAR: s += "Filter::LINEAR"; break;
+    case Filter::POINT: s += "Filter::POINT"; break;
+  }
+  return s += sfx;
+}
+
+nsACString&
+AppendToString(nsACString& s, TextureFlags flags,
+               const char* pfx, const char* sfx)
+{
+  s += pfx;
+  if (!flags) {
+    s += "NoFlags";
+  } else {
+
+#define AppendFlag(test) \
+{ \
+  if (flags & test) { \
+    if (previous) { \
+      s += "|"; \
+    } \
+    s += #test; \
+    previous = true; \
+  } \
+}
+    bool previous = false;
+    AppendFlag(TEXTURE_USE_NEAREST_FILTER);
+    AppendFlag(TEXTURE_NEEDS_Y_FLIP);
+    AppendFlag(TEXTURE_DISALLOW_BIGIMAGE);
+    AppendFlag(TEXTURE_ALLOW_REPEAT);
+    AppendFlag(TEXTURE_NEW_TILE);
+
+#undef AppendFlag
+  }
+  return s += sfx;
+}
+
+nsACString&
+AppendToString(nsACString& s, mozilla::gfx::SurfaceFormat format,
+               const char* pfx, const char* sfx)
+{
+  s += pfx;
+  switch (format) {
+  case SurfaceFormat::B8G8R8A8:  s += "SurfaceFormat::B8G8R8A8"; break;
+  case SurfaceFormat::B8G8R8X8:  s += "SurfaceFormat::B8G8R8X8"; break;
+  case SurfaceFormat::R8G8B8A8:  s += "SurfaceFormat::R8G8B8A8"; break;
+  case SurfaceFormat::R8G8B8X8:  s += "SurfaceFormat::R8G8B8X8"; break;
+  case SurfaceFormat::R5G6B5:    s += "SurfaceFormat::R5G6B5"; break;
+  case SurfaceFormat::A8:        s += "SurfaceFormat::A8"; break;
+  case SurfaceFormat::YUV:       s += "SurfaceFormat::YUV"; break;
+  case SurfaceFormat::UNKNOWN:   s += "SurfaceFormat::UNKNOWN"; break;
+  }
+
+  return s += sfx;
+}
+
+} // namespace
+} // namespace