Run GC frequently in the simulation script context, to keep memory usage down

This was SVN commit r8622.

source/scriptinterface/ScriptInterface.cpp

@@ -777,6 +777,10 @@ void ScriptInterface::DumpHeap()
 	fprintf(stderr, "# Bytes allocated after GC: %d\n", JS_GetGCParameter(m->m_rt, JSGC_BYTES));
 }
 
+void ScriptInterface::MaybeGC()
+{
+	JS_MaybeGC(m->m_cx);
+}
 
 class ValueCloner
 {

source/scriptinterface/ScriptInterface.h

@@ -253,6 +253,8 @@ public:
 	};
 #define LOCAL_ROOT_SCOPE LocalRootScope scope(GetContext()); if (! scope.OK()) return false
 
+	void MaybeGC();
+
 private:
 	bool CallFunction_(jsval val, const char* name, size_t argc, jsval* argv, jsval& ret);
 	bool Eval_(const char* code, jsval& ret);

source/simulation2/Simulation2.cpp

@@ -214,6 +214,12 @@ bool CSimulation2Impl::Update(int turnLength, const std::vector<SimulationComman
 //	if (m_TurnNumber == 0)
 //		m_ComponentManager.GetScriptInterface().DumpHeap();
 
+	// Run the GC occasionally
+	// (TODO: we ought to schedule this for a frame where we're not
+	// running the sim update, to spread the load)
+	if (m_TurnNumber % 10 == 0)
+		m_ComponentManager.GetScriptInterface().MaybeGC();
+
 	if (m_EnableOOSLog)
 		DumpState();