PPAPI generator: Ignore more date-only changes

Previously, the generator could only ignore changes in the:
// From FILENAME.idl modified DAY MON DATE TIME YEAR.
line if it was not wrapped or wrapped in a specific place. (Note this line
would otherwise change every time you generate).

This CL makes it a little better, in that it will ignore timestamp changes
regardless of where the "modified" output is wrapped. Otherwise, the generator
wants to update a few thunk files because it's now 2015. See:
https://codereview.chromium.org/849473003/
for context.

BUG=
R=bbudge@chromium.org

Review URL: https://codereview.chromium.org/849283003

Cr-Commit-Position: refs/heads/master@{#311767}

1 files changed, 9 insertions, 5 deletions

diff --git a/ppapi/generators/idl_outfile.py b/ppapi/generators/idl_outfile.py
index 053cf3e..f6a1627 100755
--- a/ppapi/generators/idl_outfile.py
+++ b/ppapi/generators/idl_outfile.py
@@ -54,6 +54,7 @@ class IDLOutFile(object):
       curwords = curline.split()
       oldwords = oldline.split()
 
+      # It wasn't a perfect match. Check for changes we should ignore.
       # Unmatched lines must be the same length
       if len(curwords) != len(oldwords):
         return False
@@ -67,16 +68,19 @@ class IDLOutFile(object):
       if len(curwords) > 4 and curwords[1] == 'Copyright':
         if curwords[4:] == oldwords[4:]: continue
 
-      # Ignore changes to auto generation timestamp when line unwrapped
+      # Ignore changes to auto generation timestamp.
       # // From FILENAME.idl modified DAY MON DATE TIME YEAR.
       # /* From FILENAME.idl modified DAY MON DATE TIME YEAR. */
-      if len(curwords) > 8 and curwords[1] == 'From':
+      # The line may be wrapped, so first deal with the first "From" line.
+      if curwords[1] == 'From':
         if curwords[0:4] == oldwords[0:4]: continue
 
       # Ignore changes to auto generation timestamp when line is wrapped
-      # * modified DAY MON DATE TIME YEAR.
-      if len(curwords) > 6 and curwords[1] == 'modified':
-        continue
+      if index > 0:
+        two_line_oldwords = oldlines[index - 1].split() + oldwords[1:]
+        two_line_curwords = curlines[index - 1].split() + curwords[1:]
+        if len(two_line_curwords) > 8 and two_line_curwords[1] == 'From':
+          if two_line_curwords[0:4] == two_line_oldwords[0:4]: continue
 
       return False
     return True