Remove scheduler code from webkit style presubmits.

Due to historical reasons scheduler uses Chromium code style instead of
Blink one. Before patch 954622 it was enforced by scheduler using
camel_case for file names.

This patch restores the exception after the said patch started to apply
webkit style checks to camel_case filenames.

TBR=dcheng@chromium.org,tkent@chromium.org

Change-Id: I7c81e7e1dfcca264f1491529c28659b6e90a3f37
Reviewed-on: https://chromium-review.googlesource.com/962422Reviewed-by: Alexander Timin <altimin@chromium.org>
Commit-Queue: Alexander Timin <altimin@chromium.org>
Cr-Commit-Position: refs/heads/master@{#543077}

third_party/WebKit/Tools/Scripts/webkitpy/style/checker.py

@@ -137,6 +137,12 @@ _PATH_RULES_SPECIFIER = [
         # than style of the machine-generated code itself.
         'Source/bindings/tests/results'],
      ['-']),
+
+    ([  # Due to historical reasons scheduler uses Chromium style instead of
+        # Blink style.
+        'Source/platform/scheduler',
+        'public/platform/scheduler'],
+     ['-readability/parameter_name'])
 ]