Revert "[FeatureList] Change GetApplicationLocale() in VariationsServiceClient to be a local function. [2/3]"

This reverts commit 08ae48ad56797b61f478f92dc243fc2dc09cccd3.

Reason for revert: crbug.com/879703, crbug.com/879547.

Original change's description:
> [FeatureList] Change GetApplicationLocale() in VariationsServiceClient to be a local function. [2/3]
>
> Before this function uses a pref in Chrome so we need to override it in Chrome
> to access that pref value.
>
> As a followup for this cl https://crrev.com/c/1135198,
> now we can access the pref directly in componment/ and we no longer need to do that.
>
> This CL comes from https://crrev.com/c/1140356. See previous discussion there.
>
> Bug:729596
> TBR=asvitkine@chromium.org
>
> Cq-Include-Trybots: luci.chromium.try:ios-simulator-cronet;luci.chromium.try:ios-simulator-full-configs;master.tryserver.chromium.mac:ios-simulator-cronet
> Change-Id: I7bf5631b81436344ccb17aaa2a8d6ac4167f5d7f
> Reviewed-on: https://chromium-review.googlesource.com/1147481
> Commit-Queue: Xi Han <hanxi@chromium.org>
> Reviewed-by: Scott Violet <sky@chromium.org>
> Reviewed-by: John Abd-El-Malek <jam@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#586711}

TBR=sky@chromium.org,jam@chromium.org,asvitkine@chromium.org,hanxi@chromium.org

# Not skipping CQ checks because original CL landed > 1 day ago.

Bug: 729596,879703,
Change-Id: I9447c4a44c5f77b6d6cbe633110895c6940d9fad
Cq-Include-Trybots: luci.chromium.try:ios-simulator-cronet;luci.chromium.try:ios-simulator-full-configs
Reviewed-on: https://chromium-review.googlesource.com/1203881
Commit-Queue: Xi Han <hanxi@chromium.org>
Reviewed-by: Xi Han <hanxi@chromium.org>
Cr-Commit-Position: refs/heads/master@{#588564}
17 files changed