SDL: Try to continue if EGL init fails.

Probably we should just stop using EGL on SDL2, but I'm not sure if
that's making things work for some users.  But if EGL init fails, try
to avoid a segfault and skip EGL.

Should help hrydgard#12474.

SDL/SDLGLGraphicsContext.cpp

@@ -23,6 +23,7 @@ static EGLSurface               g_eglSurface    = nullptr;
 static EGLNativeDisplayType     g_Display       = nullptr;
 static bool                     g_XDisplayOpen  = false;
 static EGLNativeWindowType      g_Window        = (EGLNativeWindowType)nullptr;
+static bool useEGLSwap = false;
 
 int CheckEGLErrors(const char *file, int line) {
 	EGLenum error;
@@ -328,7 +329,7 @@ int SDLGLGraphicsContext::Init(SDL_Window *&window, int x, int y, int mode, std:
 		SetGLCoreContext(true);
 #endif
 
-		window = SDL_CreateWindow("PPSSPP", x,y, pixel_xres, pixel_yres, mode);
+		window = SDL_CreateWindow("PPSSPP", x, y, pixel_xres, pixel_yres, mode);
 		if (!window) {
 			// Definitely don't shutdown here: we'll keep trying more GL versions.
 			fprintf(stderr, "SDL_CreateWindow failed for GL %d.%d: %s\n", ver.major, ver.minor, SDL_GetError());
@@ -353,7 +354,7 @@ int SDLGLGraphicsContext::Init(SDL_Window *&window, int x, int y, int mode, std:
 		SDL_GL_SetAttribute(SDL_GL_CONTEXT_MINOR_VERSION, 0);
 		SetGLCoreContext(false);
 
-		window = SDL_CreateWindow("PPSSPP", x,y, pixel_xres, pixel_yres, mode);
+		window = SDL_CreateWindow("PPSSPP", x, y, pixel_xres, pixel_yres, mode);
 		if (window == nullptr) {
 			NativeShutdown();
 			fprintf(stderr, "SDL_CreateWindow failed: %s\n", SDL_GetError());
@@ -376,11 +377,10 @@ int SDLGLGraphicsContext::Init(SDL_Window *&window, int x, int y, int mode, std:
 #ifdef USING_EGL
 	if (EGL_Open(window) != 0) {
 		printf("EGL_Open() failed\n");
-		return 1;
-	}
-	if (EGL_Init(window) != 0) {
+	} else if (EGL_Init(window) != 0) {
 		printf("EGL_Init() failed\n");
-		return 1;
+	} else {
+		useEGLSwap = true;
 	}
 #endif
 
@@ -415,7 +415,10 @@ int SDLGLGraphicsContext::Init(SDL_Window *&window, int x, int y, int mode, std:
 	assert(success);
 	renderManager_->SetSwapFunction([&]() {
 #ifdef USING_EGL
-		eglSwapBuffers(g_eglDisplay, g_eglSurface);
+		if (useEGLSwap)
+			eglSwapBuffers(g_eglDisplay, g_eglSurface);
+		else
+			SDL_GL_SwapWindow(window_);
 #else
 		SDL_GL_SwapWindow(window_);
 #endif
@@ -433,7 +436,6 @@ void SDLGLGraphicsContext::ShutdownFromRenderThread() {
 
 #ifdef USING_EGL
 	EGL_Close();
-#else
-	SDL_GL_DeleteContext(glContext);
 #endif
+	SDL_GL_DeleteContext(glContext);
 }