Remove dependency of sequenced_worker_pool.h on SingleThreadTaskRunner.
Breaks a cyclic dependency in an upcoming CL of mine.
Removing the include of single_thread_task_runner.h here breaks IWYU
all over the place!
The trickiest IWYU thing being exposed by this is that in order for
scoped_refptr<Foo> to be instantiated (not even used), Foo needs to be
fully defined.
This means that, by IWYU, anyone taking a scoped_refptr<Foo> by value or
returning one by value needs to #include "foo.h".
It's still fine to fwd-decl foo when passing via const scoped_refptr<Foo>&
or having a scoped_refptr<Foo> foo_; member in a class constructed/destroyed
out-of-line.
BUG=653916
CQ_INCLUDE_TRYBOTS=master.tryserver.blink:linux_precise_blink_rel
TBR=reviewers for IWUU side-effects (and minor other touchups):
kmarshall@: blimp/
danakj@: cc/
storage/
bartfab@: chrome/browser/chromeos/policy/
gene@: chrome/service/
maxbogue@: components/browser_sync/
components/sync/
bengr@: components/data_reduction_proxy/
fukino@: components/drive/
dimich@: components/gcm_driver/
bradnelson@: components/nacl/
achuith@: components/pairing/
rsesek@: components/upload_list/
mef@: components/wifi/
michaeln@: content/browser/cache_storage/
content/child/fileapi/
dgozman@: content/browser/devtools/
csharrison@: content/browser/loader/
hbos@: content/renderer/media/
mkwst@: content/shell/
pfeldman@: device/usb/
kbr@: gpu/
droger@: ios/
rockot@: ipc/
dalecurtis@: media/
agl@: net/
garykac@: remoting/
erg@: services/ui/
dglazkov@: third_party/WebKit/Source/platform/
Review-Url: https://codereview.chromium.org/2443103003
Cr-Commit-Position: refs/heads/master@{#429451}
90 files changed
