Reset window size on initialization

On macOS with renderer "metal", HiDPI scaling may be incorrect on
initialization when several displays are connected.

Resetting the window size fixes the problem.

Refs #15 <https://github.com/Genymobile/scrcpy/issues/15>

app/src/screen.c

@@ -162,15 +162,10 @@ screen_update_content_rect(struct screen *screen) {
     int dh;
     SDL_GL_GetDrawableSize(screen->window, &dw, &dh);
 
-    int ww, wh;
-    SDL_GetWindowSize(screen->window, &ww, &wh);
-
     struct size content_size = screen->content_size;
     // The drawable size is the window size * the HiDPI scale
     struct size drawable_size = {dw, dh};
 
-    LOGI("update_content_rect: window=%dx%d, drawable=%dx%d content=%ux%u", ww, wh, dw, dh, content_size.width, content_size.height);
-
     SDL_Rect *rect = &screen->rect;
 
     if (is_optimal_size(drawable_size, content_size)) {
@@ -178,7 +173,6 @@ screen_update_content_rect(struct screen *screen) {
         rect->y = 0;
         rect->w = drawable_size.width;
         rect->h = drawable_size.height;
-        LOGI("  --> (optimal) rect (%d, %d) %dx%d", rect->x, rect->y, rect->w, rect->h);
         return;
     }
 
@@ -197,8 +191,6 @@ screen_update_content_rect(struct screen *screen) {
                                        / content_size.height;
         rect->x = (drawable_size.width - rect->w) / 2;
     }
-
-    LOGI("  --> rect (%d, %d) %dx%d", rect->x, rect->y, rect->w, rect->h);
 }
 
 void
@@ -333,6 +325,9 @@ screen_init_rendering(struct screen *screen, const char *window_title,
         return false;
     }
 
+    // Reset the window size to trigger a SIZE_CHANGED event, to workaround
+    // HiDPI issues with some SDL renderers when several displays having
+    // different HiDPI scaling are connected
     SDL_SetWindowSize(screen->window, window_size.width, window_size.height);
 
     screen_update_content_rect(screen);
@@ -561,19 +556,15 @@ screen_handle_window_event(struct screen *screen,
                            const SDL_WindowEvent *event) {
     switch (event->event) {
         case SDL_WINDOWEVENT_EXPOSED:
-            LOGI("EXPOSED");
             screen_render(screen, true);
             break;
         case SDL_WINDOWEVENT_SIZE_CHANGED:
-            LOGI("SIZE_CHANGED %dx%d", event->data1, event->data2);
             screen_render(screen, true);
             break;
         case SDL_WINDOWEVENT_MAXIMIZED:
-            LOGI("MAXIMIZED");
             screen->maximized = true;
             break;
         case SDL_WINDOWEVENT_RESTORED:
-            LOGI("RESTORED");
             if (screen->fullscreen) {
                 // On Windows, in maximized+fullscreen, disabling fullscreen
                 // mode unexpectedly triggers the "restored" then "maximized"