message: Fix missing call to glInvalidateFramebuffer().
  We were over-optimizing, not always honoring the flag. This was
  incorrect since bindFramebuffer can be called from other places.
  Fixes
diff: @@ -1889,7 +1889,6 @@ void OpenGLDriver::beginRenderPass(Handle<HwRenderTarget> rth,
  TargetBufferFlags discardFlags = params.flags.discardStart;
  GLRenderTarget* rt = handle_cast<GLRenderTarget*>(rth);
  - if (UTILS_UNLIKELY(gl.getDrawFbo() != rt->gl.fbo)) {
  gl.bindFramebuffer(GL_FRAMEBUFFER, rt->gl.fbo);
  // glInvalidateFramebuffer appeared on GLES 3.0 and GL4.3, for simplicity we just
  @@ -1904,7 +1903,6 @@ void OpenGLDriver::beginRenderPass(Handle<HwRenderTarget> rth,
  CHECK_GL_ERROR(utils::slog.e)
  }
  }
  - }
  if (rt->gl.fbo_read) {
  // we have a multi-sample RenderTarget with non multi-sample attachments (i.e. this is the
  