Remove D3D9 fallback path (flutter#29533)

Author: George Wright

shell/platform/windows/angle_surface_manager.cc

@@ -122,20 +122,10 @@ bool AngleSurfaceManager::Initialize() {
  EGL_NONE,
  };
 
- // These are used to request ANGLE's D3D9 renderer as a fallback if D3D11
- // is not available.
- const EGLint d3d9_display_attributes[] = {
- EGL_PLATFORM_ANGLE_TYPE_ANGLE,
- EGL_PLATFORM_ANGLE_TYPE_D3D9_ANGLE,
- EGL_TRUE,
- EGL_NONE,
- };
-
  std::vector<const EGLint*> display_attributes_configs = {
  d3d11_display_attributes,
  d3d11_fl_9_3_display_attributes,
  d3d11_warp_display_attributes,
- d3d9_display_attributes,
  };
 
  PFNEGLGETPLATFORMDISPLAYEXTPROC egl_get_platform_display_EXT =
@@ -147,7 +137,7 @@ bool AngleSurfaceManager::Initialize() {
  }
 
  // Attempt to initialize ANGLE's renderer in order of: D3D11, D3D11 Feature
- // Level 9_3, D3D11 WARP and finally D3D9.
+ // Level 9_3 and finally D3D11 WARP.
  for (auto config : display_attributes_configs) {
  bool should_log = (config == display_attributes_configs.back());
  if (InitializeEGL(egl_get_platform_display_EXT, config, should_log)) {