Revert "[ChromeDriver] Fix path for old Chromium snapshots"

This reverts commit 306be5bf.

Reason for revert: GS bucket names have been fixed

Original change's description:
> [ChromeDriver] Fix path for old Chromium snapshots
> 
> Chromium snapshots before revision 579575 are still archived using
> the old directory name.
> 
> TBR=crouleau@chromium.org
> 
> Change-Id: I4cc1e9ca51af9f8f21e22214af2110a6d8be8fe7
> Reviewed-on: https://chromium-review.googlesource.com/1158709
> Reviewed-by: John Chen <johnchen@chromium.org>
> Commit-Queue: John Chen <johnchen@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#579802}

TBR=crouleau@chromium.org,johnchen@chromium.org

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

Change-Id: I093548f1d0ef02a37ffd8d3d2fe66f7222234e1b
Reviewed-on: https://chromium-review.googlesource.com/1171426Reviewed-by: Stephen Martinis <martiniss@chromium.org>
Reviewed-by: Caleb Rouleau <crouleau@chromium.org>
Commit-Queue: Stephen Martinis <martiniss@chromium.org>
Cr-Commit-Position: refs/heads/master@{#582338}

chrome/test/chromedriver/archive.py

@@ -70,29 +70,15 @@ def DownloadChrome(revision, dest_dir, site=Site.CHROMIUM_SNAPSHOT):
 
   zip_path = os.path.join(dest_dir, 'chrome-%s.zip' % revision)
   if not os.path.exists(zip_path):
-    legacy = int(revision) < 579575
-    url = site + '/%s/%s' % (_GetDownloadPlatform(legacy), GetZipName(revision))
+    url = site + '/%s/%s' % (_GetDownloadPlatform(), GetZipName(revision))
     print 'Downloading', url, '...'
     urllib.urlretrieve(url, zip_path)
   util.Unzip(zip_path, dest_dir)
   return os.path.join(dest_dir, GetDirName(), GetChromePathFromPackage())
 
 
-def _GetDownloadPlatform(legacy=False):
-  """Returns the name for this platform on the archive site.
-
-  Args:
-    legacy: When True, return name used for builds before revision 579575.
-            TODO(johnchen@chromium.org): Remove when we stop supporting m69.
-  """
-  if legacy:
-    if util.IsWindows():
-      return 'Win'
-    elif util.IsMac():
-      return 'Mac'
-    elif util.IsLinux():
-      return 'Linux_x64'
-
+def _GetDownloadPlatform():
+  """Returns the name for this platform on the archive site."""
   if util.IsWindows():
     return 'win32_rel'
   elif util.IsMac():