D3D9.dll is being loaded by ANGLE when using D3D11. This change
removes the D3D9 dependency.

- Delayload D3D9.dll using ldflags in BUILD.gn

- Replace Renderer11 usage of DebugAnnotator9 with DebugAnnotator11.
Using debug annotations with Visual Studio PIX tools now requires Windows 10.

- Refactor DebugAnnotator11 to QI ID3DUserDefinedAnnotation from the
renderer's ID3D11DeviceContext instead of making a 'null' device.

Bug: angleproject:3234
Change-Id: I10a2b537e07cda2094b08abf02b7876bbe5009f8
Reviewed-on: https://chromium-review.googlesource.com/c/angle/angle/+/1508643
Commit-Queue: Rafael Cintron <rafael.cintron@microsoft.com>
Reviewed-by: Jamie Madill <jmadill@chromium.org>