Bug 1666802 - Modify the ScrollPositionUpdate serializer to write to an ostream directly. r=mattwoodrow

Differential Revision: https://phabricator.services.mozilla.com/D93142

gfx/layers/LayersLogging.cpp

@@ -191,14 +191,6 @@ void AppendToString(std::stringstream& aStream, ImageFormat format,
   aStream << sfx;
 }
 
-void AppendToString(std::stringstream& aStream,
-                    const mozilla::ScrollPositionUpdate& aUpdate,
-                    const char* pfx, const char* sfx) {
-  aStream << pfx;
-  aUpdate.AppendToString(aStream);
-  aStream << sfx;
-}
-
 }  // namespace layers
 }  // namespace mozilla
 

gfx/layers/LayersLogging.h

@@ -45,10 +45,6 @@ void AppendToString(std::stringstream& aStream, gfx::SurfaceType format,
 void AppendToString(std::stringstream& aStream, ImageFormat format,
                     const char* pfx = "", const char* sfx = "");
 
-void AppendToString(std::stringstream& aStream,
-                    const mozilla::ScrollPositionUpdate& aUpdate,
-                    const char* pfx = "", const char* sfx = "");
-
 // Sometimes, you just want a string from a single value.
 template <typename T>
 std::string Stringify(const T& obj) {

gfx/layers/apz/src/AsyncPanZoomController.cpp

@@ -4706,7 +4706,7 @@ void AsyncPanZoomController::NotifyLayersUpdated(
   bool scrollOffsetUpdated = false;
   for (const auto& scrollUpdate : aScrollMetadata.GetScrollUpdates()) {
     APZC_LOG("%p processing scroll update %s\n", this,
-             Stringify(scrollUpdate).c_str());
+             ToString(scrollUpdate).c_str());
     if (scrollUpdate.GetGeneration() <= Metrics().GetScrollGeneration()) {
       // This is stale, let's ignore it
       // XXX maybe use a 64-bit value for the scroll generation, or add some

layout/generic/ScrollPositionUpdate.cpp

@@ -4,6 +4,8 @@
 
 #include "ScrollPositionUpdate.h"
 
+#include <ostream>
+
 #include "mozilla/Assertions.h"
 
 namespace mozilla {
@@ -117,12 +119,15 @@ CSSPoint ScrollPositionUpdate::GetDelta() const {
   return mDelta;
 }
 
-void ScrollPositionUpdate::AppendToString(std::stringstream& aStream) const {
+std::ostream& operator<<(std::ostream& aStream,
-  aStream << "ScrollPositionUpdate(gen=" << mScrollGeneration
+                         const ScrollPositionUpdate& aUpdate) {
-          << ", type=" << (int)mType << ", mode=" << (int)mScrollMode
+  aStream << "{ gen=" << aUpdate.mScrollGeneration
-          << ", origin=" << (int)mScrollOrigin << ", dst=" << mDestination.x
+          << ", type=" << (int)aUpdate.mType
-          << "," << mDestination.y << ", src=" << mSource.x << "," << mSource.y
+          << ", mode=" << (int)aUpdate.mScrollMode
-          << ", delta=" << mDelta.x << "," << mDelta.y << ")";
+          << ", origin=" << (int)aUpdate.mScrollOrigin
+          << ", dst=" << aUpdate.mDestination << ", src=" << aUpdate.mSource
+          << ", delta=" << aUpdate.mDelta << " }";
+  return aStream;
 }
 
 }  // namespace mozilla

layout/generic/ScrollPositionUpdate.h

@@ -6,6 +6,7 @@
 #define mozilla_ScrollPositionUpdate_h_
 
 #include <cstdint>
+#include <iosfwd>
 
 #include "nsPoint.h"
 #include "mozilla/ScrollOrigin.h"
@@ -83,7 +84,8 @@ class ScrollPositionUpdate {
   // GetDelta is only valid for the PureRelative type; it asserts otherwise.
   CSSPoint GetDelta() const;
 
-  void AppendToString(std::stringstream& aStream) const;
+  friend std::ostream& operator<<(std::ostream& aStream,
+                                  const ScrollPositionUpdate& aUpdate);
 
  private:
   uint32_t mScrollGeneration;