D3D: Add exclusive fullscreen support.

Source/Core/DolphinWX/Frame.cpp

@@ -1206,6 +1206,8 @@ void CFrame::DoFullscreen(bool bF)
 	{
 		m_RenderFrame->Raise();
 	}
+
+	g_Config.bFullscreen = bF;
 }
 
 const CGameListCtrl *CFrame::GetGameListCtrl() const

Source/Core/VideoBackends/D3D/D3DBase.cpp

@@ -431,6 +431,9 @@ void Reset()
 	// release all back buffer references
 	SAFE_RELEASE(backbuf);
 
+	// apply fullscreen state
+	D3D::swapchain->SetFullscreenState(g_ActiveConfig.bFullscreen, nullptr);
+
 	// resize swapchain buffers
 	RECT client;
 	GetClientRect(hWnd, &client);

Source/Core/VideoBackends/D3D/Render.cpp

@@ -42,6 +42,8 @@ static u32 s_LastAA = 0;
 
 static Television s_television;
 
+static bool s_LastFS = false;
+
 ID3D11Buffer* access_efb_cbuf = nullptr;
 ID3D11BlendState* clearblendstates[4] = {nullptr};
 ID3D11DepthStencilState* cleardepthstates[3] = {nullptr};
@@ -936,6 +938,8 @@ void Renderer::SwapImpl(u32 xfbAddr, u32 fbWidth, u32 fbHeight,const EFBRectangl
 	SetWindowSize(fbWidth, fbHeight);
 
 	const bool windowResized = CheckForResize();
+	const bool fullscreen = g_ActiveConfig.bFullscreen;
+	const bool fsChanged = s_LastFS != fullscreen;
 
 	bool xfbchanged = false;
 
@@ -954,13 +958,15 @@ void Renderer::SwapImpl(u32 xfbAddr, u32 fbWidth, u32 fbHeight,const EFBRectangl
 	// resize the back buffers NOW to avoid flickering
 	if (xfbchanged ||
 		windowResized ||
+		fsChanged ||
 		s_LastEFBScale != g_ActiveConfig.iEFBScale ||
 		s_LastAA != g_ActiveConfig.iMultisampleMode)
 	{
 		s_LastAA = g_ActiveConfig.iMultisampleMode;
+		s_LastFS = g_ActiveConfig.bFullscreen;
 		PixelShaderCache::InvalidateMSAAShaders();
 
-		if (windowResized)
+		if (windowResized || fsChanged)
 		{
 			// TODO: Aren't we still holding a reference to the back buffer right now?
 			D3D::Reset();

Source/Core/VideoCommon/VideoConfig.cpp

@@ -28,6 +28,7 @@ void UpdateActiveConfig()
 VideoConfig::VideoConfig()
 {
 	bRunning = false;
+	bFullscreen = false;
 
 	// Needed for the first frame, I think
 	fAspectRatioHackW = 1;

Source/Core/VideoCommon/VideoConfig.h

@@ -57,7 +57,7 @@ struct VideoConfig final
 
 	// General
 	bool bVSync;
-
+	bool bFullscreen;
 	bool bRunning;
 	bool bWidescreenHack;
 	int iAspectRatio;