Out-of-Memory condition when zooming into Google Maps too quickly

WebKit bug: https://bugs.webkit.org/show_bug.cgi?id=105158

When Google Maps is zoomed in quickly, you end up with a very, very large div before new tiles can be brought down to replace it. During that time, when GraphicsLayerTextureMapper updates its backing store, the TextureMapperTiledBackingStore::createOrDestroyTilesIfNeeded() method attempts to allocate massive tiles, leading to allocation of several Gb of RAM, and the browser process gets killed by the kernel OOM killer.

It seems that WebKit is planning to replace TextureMapperTiledBackingStore with Composite Graphics from WebKit 2 (see https://bugs.webkit.org/show_bug.cgi?id=102994), but I guess this hasn't landed yet.

I can't use WebKit 2 via QtQuick, because I need features that aren't available through that API yet.