[Fuchsia] Remove Swapchain dependency

Vulkan Swapchain is no longer being used on Fuchsia. Updated Scenic
ozone backend to load swapchain layer and extension only when they are
included into the package. Removed swapchain dependency from WebEngine.

Bug: 1203879
Change-Id: I250bb89e2df0903fe73e596c5a02b7b6a308a74e
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/3011909
Commit-Queue: Sergey Ulanov <sergeyu@chromium.org>
Reviewed-by: Peng Huang <penghuang@chromium.org>
Reviewed-by: Michael Spang <spang@chromium.org>
Reviewed-by: Andrew Grieve <agrieve@chromium.org>
Cr-Commit-Position: refs/heads/master@{#900215}
NOKEYCHECK=True
GitOrigin-RevId: 60e3cbbf3615239f393277318500be655b5686e6
1 file changed
tree: 338c5fc582267426fe0dd18068f8917367747ba3
  1. BUILD.gn
  2. DIR_METADATA
  3. OWNERS
  4. README.chromium