Minor GPU interface change needed for a WIP backend

Core/System.cpp

@@ -486,10 +486,15 @@ void PSP_Shutdown() {
 
 void PSP_BeginHostFrame() {
 	// Reapply the graphics state of the PSP
-	gpu->ReapplyGfxState();
+	if (gpu) {
+		gpu->BeginHostFrame();
+	}
 }
 
 void PSP_EndHostFrame() {
+	if (gpu) {
+		gpu->EndHostFrame();
+	}
 }
 
 void PSP_RunLoopUntil(u64 globalticks) {

GPU/GPUCommon.cpp

@@ -40,6 +40,14 @@ GPUCommon::GPUCommon() :
 GPUCommon::~GPUCommon() {
 }
 
+void GPUCommon::BeginHostFrame() {
+	ReapplyGfxState();
+}
+
+void GPUCommon::EndHostFrame() {
+
+}
+
 void GPUCommon::Reinitialize() {
 	easy_guard guard(listLock);
 	memset(dls, 0, sizeof(dls));

GPU/GPUCommon.h

@@ -21,6 +21,9 @@ public:
 
 	void Reinitialize() override;
 
+	void BeginHostFrame() override;
+	void EndHostFrame() override;
+
 	void InterruptStart(int listid) override;
 	void InterruptEnd(int listid) override;
 	void SyncEnd(GPUSyncType waitType, int listid, bool wokeThreads) override;

GPU/GPUInterface.h

@@ -214,6 +214,11 @@ public:
 	virtual void InitClear() = 0;
 	virtual void Reinitialize() = 0;
 
+	// Frame managment
+	virtual void BeginHostFrame() = 0;
+	virtual void EndHostFrame() = 0;
+
+	// Events
 	virtual void RunEventsUntil(u64 globalticks) = 0;
 	virtual void FinishEventLoop() = 0;