Revert "Fix checkout.py issues when p.patchlevel > 1."

This reverts commit 5908f9906dc71c0229c2e359fd64b325605b8370.

Reason for revert:
Introduces bugs when deleting files.
The reason is that 
  patchlevel = patchlevel or self.patchlevel
will evaluate to self.patchlevel also when patchlevel is 0, which is wrong.

Original change's description:
> Fix checkout.py issues when p.patchlevel > 1.
> 
> When p.patchlevel > 1, p.filename does not correspond to the files that
> git-apply would modify.
> 
> See bug for details
> 
> Bug: 764294
> Change-Id: Icdb803056e306edb25238b2d9cdabd3ff175d8ed
> Reviewed-on: https://chromium-review.googlesource.com/663357
> Reviewed-by: Aaron Gable <agable@chromium.org>
> Commit-Queue: Edward Lesmes <ehmaldonado@chromium.org>

TBR=kjellander@chromium.org,agable@chromium.org,ehmaldonado@chromium.org

Change-Id: Ifa1f94602a023228cb32e5fe3fa07586b466981a
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Bug: 764294
Reviewed-on: https://chromium-review.googlesource.com/663266
Reviewed-by: Edward Lesmes <ehmaldonado@chromium.org>
Commit-Queue: Edward Lesmes <ehmaldonado@chromium.org>
diff --git a/checkout.py b/checkout.py
index c5e61dd..4a59000 100644
--- a/checkout.py
+++ b/checkout.py
@@ -252,8 +252,7 @@
     for index, p in enumerate(patches):
       stdout = []
       try:
-        filepath = os.path.join(self.project_path,
-                                p.filename_after_patchlevel())
+        filepath = os.path.join(self.project_path, p.filename)
         if p.is_delete:
           if (not os.path.exists(filepath) and
               any(p1.source_filename == p.filename for p1 in patches[0:index])):
@@ -261,12 +260,11 @@
             # was already processed because 'git apply' did it for us.
             pass
           else:
-            stdout.append(self._check_output_git(
-                ['rm', p.filename_after_patchlevel()]))
+            stdout.append(self._check_output_git(['rm', p.filename]))
             assert(not os.path.exists(filepath))
             stdout.append('Deleted.')
         else:
-          dirname = os.path.dirname(p.filename_after_patchlevel())
+          dirname = os.path.dirname(p.filename)
           full_dir = os.path.join(self.project_path, dirname)
           if dirname and not os.path.isdir(full_dir):
             os.makedirs(full_dir)
@@ -276,7 +274,7 @@
             with open(filepath, 'wb') as f:
               f.write(content)
             stdout.append('Added binary file %d bytes' % len(content))
-            cmd = ['add', p.filename_after_patchlevel()]
+            cmd = ['add', p.filename]
             if verbose:
               cmd.append('--verbose')
             stdout.append(self._check_output_git(cmd))