Added check for trailing whitespaces and corrected existing violations.

tools/presubmit.py

Index: tools/presubmit.py
diff --git a/tools/presubmit.py b/tools/presubmit.py
index c191fc7497045d86794078badcb5b685b278ea77..e3bc1559e2d1575bcf78c4cfae49f580a7da9ae4 100755
--- a/tools/presubmit.py
+++ b/tools/presubmit.py
@@ -231,11 +231,11 @@ COPYRIGHT_HEADER_PATTERN = re.compile(
 
 class SourceProcessor(SourceFileProcessor):
   """
-  Check that all files include a copyright notice.
+  Check that all files include a copyright notice and trailing whitespaces.

[Jakob Kummerow, 2011/09/01 09:29:46]

you mean "and *no* trailing whitespace", right?

   """
 
   RELEVANT_EXTENSIONS = ['.js', '.cc', '.h', '.py', '.c', 'SConscript',
-      'SConstruct', '.status']
+      'SConstruct', '.status', '.gyp', '.gypi']
   def IsRelevant(self, name):
     for ext in SourceProcessor.RELEVANT_EXTENSIONS:
       if name.endswith(ext):
@@ -273,6 +273,18 @@ class SourceProcessor(SourceFileProcessor):
       if not COPYRIGHT_HEADER_PATTERN.search(contents):
         print "%s is missing a correct copyright header." % name
         result = False
+    if ' \n' in contents or contents.endswith(' '):

[Jakob Kummerow, 2011/09/01 09:29:46]

The "contents.endswith(' ')" case isn't handled below.

+      line = 0
+      lines = []
+      for part in contents.split(' \n')[0:-1]:
+        line += part.count('\n') + 1;
+        lines.append(str(line));
+      linenumbers = ', '.join(lines);
+      if len(lines) > 1:
+        print "%s has trailing whitespaces in lines: %s" % (name, linenumbers)

[Kevin Millikin (Chromium), 2011/09/01 09:32:21]

There is already a check for trailing whitespace for C++ files, so won't we now
get two warnings for C++ files?  You might consider disabling
whitespace/end_of_line.

+      else:
+        print "%s has trailing whitespaces in line %s" % (name, linenumbers)
+      result = False
     return result
 
   def ProcessFiles(self, files, path):