Bug 1353998 - Start measuring Stylo style sheet memory usage. r=heycam.

--HG--
extra : rebase_source : 85f83566643e7b4c2276f0bf3fbb1a907f58fe0e

layout/style/ServoBindingList.h

@@ -50,6 +50,8 @@ SERVO_BINDING_FUNC(Servo_StyleSheet_GetRules, ServoCssRulesStrong,
                    RawServoStyleSheetBorrowed sheet)
 SERVO_BINDING_FUNC(Servo_StyleSheet_Clone, RawServoStyleSheetStrong,
                    RawServoStyleSheetBorrowed sheet)
+SERVO_BINDING_FUNC(Servo_StyleSheet_SizeOfIncludingThis, size_t,
+                   mozilla::MallocSizeOf malloc_size_of, RawServoStyleSheetBorrowed sheet)
 SERVO_BINDING_FUNC(Servo_StyleSet_Init, RawServoStyleSetOwned, RawGeckoPresContextOwned pres_context)
 SERVO_BINDING_FUNC(Servo_StyleSet_Clear, void,
                    RawServoStyleSetBorrowed set)

layout/style/ServoBindings.toml

@@ -321,6 +321,7 @@ structs-types = [
     "mozilla::css::GridTemplateAreasValue",
     "mozilla::css::ImageValue",
     "mozilla::css::URLValue",
+    "mozilla::MallocSizeOf",
     "mozilla::Side",
     "RawGeckoAnimationPropertySegment",
     "RawGeckoComputedTiming",

layout/style/ServoStyleSheet.cpp

@@ -59,13 +59,13 @@ ServoStyleSheetInner::CloneFor(StyleSheet* aPrimarySheet)
                                   static_cast<ServoStyleSheet*>(aPrimarySheet));
 }
 
+MOZ_DEFINE_MALLOC_SIZE_OF(ServoStyleSheetMallocSizeOf)
+
 size_t
 ServoStyleSheetInner::SizeOfIncludingThis(MallocSizeOf aMallocSizeOf) const
 {
   size_t n = aMallocSizeOf(this);
-
-  // XXX: need to measure mSheet
-
+  n += Servo_StyleSheet_SizeOfIncludingThis(ServoStyleSheetMallocSizeOf, mSheet);
   return n;
 }