Remove the include guard rule in Blink C++ style

Now we use Chromium-style include guard even in Blink.
Update check-webkit-style so that it doesn't accept WebKit-style include
guard.

Bug: 768828
Change-Id: Iea94b1857fc735fc8767b86c56156110ad6c2364
Reviewed-on: https://chromium-review.googlesource.com/1002344
Commit-Queue: Nico Weber <thakis@chromium.org>
Reviewed-by: Nico Weber <thakis@chromium.org>
Cr-Commit-Position: refs/heads/master@{#549153}

styleguide/c++/blink-c++.md

@@ -49,9 +49,9 @@ FrameLoader::FrameLoader(LocalFrame* frame)
 
 ## Prefer WTF types over STL types
 
-Outside of `//third_party/WebKit/common`, Blink should use WTF types. STL string
+Outside of `//third_party/blink/common`, Blink should use WTF types. STL string
 and container types should only be used at the boundary to interoperate with
-'//base', `//third_party/WebKit/common`, and other Chromium-side code.
+'//base', `//third_party/blink/common`, and other Chromium-side code.
 Similarly, Blink should prefer `KURL` over `GURL` and `SecurityOrigin` over
 `url::Origin`.
 
@@ -69,33 +69,6 @@ Similarly, Blink should prefer `KURL` over `GURL` and `SecurityOrigin` over
   std::unordered_map<int, std::deque<url::Origin>> origins;
 ```
 
-## Use Filename_h as the header include guard
-
-Header include guards in Blink should match the filename exactly, replacing the
-“.” with a “\_”.
-
-**Good:**
-```c++
-// third_party/WebKit/Source/core/html/HTMLDocument.h
-#ifndef HTMLDocument_h
-#define HTMLDocument_h
-
-// ...
-
-#endif  // HTMLDocument_h
-```
-
-**Bad:**
-```c++
-// third_party/WebKit/Source/core/html/HTMLDocument.h
-#ifndef THIRD_PARTY_WEBKIT_SOURCE_CORE_HTML_HTMLDOCUMENT_H_
-#define THIRD_PARTY_WEBKIT_SOURCE_CORE_HTML_HTMLDOCUMENT_H_
-
-// ...
-
-#endif  // THIRD_PARTY_WEBKIT_SOURCE_CORE_HTML_HTMLDOCUMENT_H_
-```
-
 ## Naming
 
 ### Use `CamelCase` for all function names

third_party/WebKit/Tools/Scripts/webkitpy/style/checkers/cpp.py

@@ -773,35 +773,6 @@ def check_for_copyright(lines, error):
               'You should have a line: "Copyright [year] <Copyright Owner>"')
 
 
-# TODO(jww) After the transition of Blink into the Chromium repo, this function
-# should be removed. This will strictly enforce Chromium-style header guards,
-# rather than allowing traditional WebKit header guards and Chromium-style
-# simultaneously.
-def get_legacy_header_guard_cpp_variable(filename):
-    """Returns the CPP variable that should be used as a header guard.
-
-    Args:
-      filename: The name of a C++ header file.
-
-    Returns:
-      The CPP variable that should be used as a header guard in the
-      named file.
-    """
-
-    # Restores original filename in case that style checker is invoked from Emacs's
-    # flymake.
-    filename = re.sub(r'_flymake\.h$', '.h', filename)
-
-    standard_name = sub(r'[-.\s]', '_', os.path.basename(filename))
-
-    # Files under WTF typically have header guards that start with WTF_.
-    if '/wtf/' in filename:
-        special_name = 'WTF_' + standard_name
-    else:
-        special_name = standard_name
-    return (special_name, standard_name)
-
-
 def get_header_guard_cpp_variable(filename):
     """Returns the CPP variable that should be used as a header guard in Chromium-style.
 
@@ -817,13 +788,7 @@ def get_header_guard_cpp_variable(filename):
     # flymake.
     filename = re.sub(r'_flymake\.h$', '.h', filename)
 
-    # If it's a full path and starts with Source/, replace Source with blink
-    # since that will be the new style directory.
-    filename = sub(r'^Source\/', 'blink/', filename)
-
-    standard_name = sub(r'[-.\s\/]', '_', filename).upper() + '_'
-
-    return standard_name
+    return sub(r'[-.\s\/]', '_', filename).upper() + '_'
 
 
 def check_for_header_guard(filename, clean_lines, error):
@@ -839,9 +804,7 @@ def check_for_header_guard(filename, clean_lines, error):
     """
     raw_lines = clean_lines.lines_without_raw_strings
 
-    legacy_cpp_var = get_legacy_header_guard_cpp_variable(filename)
     cpp_var = get_header_guard_cpp_variable(filename)
-    suggested_var = legacy_cpp_var[0] if re.search(r'[A-Z]', os.path.basename(filename)) else cpp_var
 
     ifndef = None
     ifndef_line_number = 0
@@ -862,13 +825,13 @@ def check_for_header_guard(filename, clean_lines, error):
     if not ifndef or not define or ifndef != define:
         error(0, 'build/header_guard', 5,
               'No #ifndef header guard found, suggested CPP variable is: %s' %
-              suggested_var)
+              cpp_var)
         return
 
     # The guard should be File_h or, for Chromium style, BLINK_PATH_TO_FILE_H_.
-    if ifndef not in legacy_cpp_var and ifndef != cpp_var:
+    if ifndef != cpp_var:
         error(ifndef_line_number, 'build/header_guard', 5,
-              '#ifndef header guard has wrong style, please use: %s' % suggested_var)
+              '#ifndef header guard has wrong style, please use: %s' % cpp_var)
 
 
 def check_for_unicode_replacement_characters(lines, error):

third_party/WebKit/Tools/Scripts/webkitpy/style/checkers/cpp_unittest.py

@@ -1420,45 +1420,17 @@ class CppStyleTest(CppStyleTestBase):
         # Verify that we don't blindly suggest the WTF prefix for all headers.
         self.assertFalse(expected_guard.startswith('WTF_'))
 
-        # Allow the WTF_ prefix for files in that directory.
+        # Verify that the Chromium-style header guard is allowed.
         header_guard_filter = FilterConfiguration(('-', '+build/header_guard'))
         error_collector = ErrorCollector(self.assertTrue, header_guard_filter)
-        self.process_file_data('Source/JavaScriptCore/wtf/TestName.h', 'h',
-                               ['#ifndef WTF_TestName_h', '#define WTF_TestName_h'],
-                               error_collector)
-        self.assertEqual(0, len(error_collector.result_list()),
-                         error_collector.result_list())
-
-        # Also allow the non WTF_ prefix for files in that directory.
-        error_collector = ErrorCollector(self.assertTrue, header_guard_filter)
-        self.process_file_data('Source/JavaScriptCore/wtf/TestName.h', 'h',
-                               ['#ifndef TestName_h', '#define TestName_h'],
-                               error_collector)
-        self.assertEqual(0, len(error_collector.result_list()),
-                         error_collector.result_list())
-
-        # Verify that we suggest the WTF prefix version.
-        error_collector = ErrorCollector(self.assertTrue, header_guard_filter)
-        self.process_file_data('Source/JavaScriptCore/wtf/TestName.h', 'h',
-                               ['#ifndef BAD_TestName_h', '#define BAD_TestName_h'],
-                               error_collector)
-        self.assertEqual(
-            1,
-            error_collector.result_list().count(
-                '#ifndef header guard has wrong style, please use: WTF_TestName_h'
-                '  [build/header_guard] [5]'),
-            error_collector.result_list())
-
-        # Verify that the Chromium-style header guard is allowed as well.
-        error_collector = ErrorCollector(self.assertTrue, header_guard_filter)
         self.process_file_data('Source/foo/testname.h', 'h',
-                               ['#ifndef BLINK_FOO_TESTNAME_H_',
-                                '#define BLINK_FOO_TESTNAME_H_'],
+                               ['#ifndef SOURCE_FOO_TESTNAME_H_',
+                                '#define SOURCE_FOO_TESTNAME_H_'],
                                error_collector)
         self.assertEqual(0, len(error_collector.result_list()),
                          error_collector.result_list())
 
-        # Verify that we suggest the Chromium-style header guard for a snake_case file.
+        # Verify that we suggest the Chromium-style header guard.
         error_collector = ErrorCollector(self.assertTrue, header_guard_filter)
         self.process_file_data('renderer/platform/wtf/auto_reset.h', 'h',
                                ['#ifndef BAD_auto_reset_h', '#define BAD_auto_reset_h'],