Fixing ResourceType build dependencies

The mojo type ResourceType used the public resource_type.h
header without depending on the build target where that header
was declared. Depending directly on that target would
create a dependency cycle so a new "resource_type_header" target
was created.

The dependency cycle would have been:
//content/public/common:resource_type_bindings ->
//content/public/common:common ->
//content:content
//content/public/app:both_sources ->
//content/public/common:common_sources ->
//content/public/common:interfaces ->
//content/public/common:resource_type_bindings ->

The exact error this fixes is:

ERROR at //out/Default/gen/content/public/common/resource_type.mojom-forward.h:35:11: Include not allowed.
          ^------------------------------------
It is not in any dependency of
  //content/public/common:resource_type_bindings
The include file is in the target(s):
  //content/public/common:common_sources
which should somehow be reachable.
___________________

Bug 938893

Change-Id: I350bff6a53a5be72f992e1226f7a3adce46f709d
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1535856
Reviewed-by: Kinuko Yasuda <kinuko@chromium.org>
Commit-Queue: Daniel Bratell <bratell@opera.com>
Cr-Commit-Position: refs/heads/master@{#644358}
2 files changed