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- Move Type to a new mojo file to avoid cyclic dependendency
- Add dependency from ShareTarget to mojom and vice versa

Bug: 1085068
Change-Id: I0e358270afda02758c303967ee6b6f5b4fbce8c0
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2330025
Commit-Queue: Himanshu Jaju <himanshujaju@chromium.org>
Reviewed-by: Alex Gough <ajgo@chromium.org>
Reviewed-by: Richard Knoll <knollr@chromium.org>
Cr-Commit-Position: refs/heads/master@{#793568}