grit: In generated _map.cc files, use relative includes.

tools/grit/grit/format/resource_map.py

Index: tools/grit/grit/format/resource_map.py
diff --git a/tools/grit/grit/format/resource_map.py b/tools/grit/grit/format/resource_map.py
index aca302b79f04fe8f6a0a1f48645003dbbdfa5c8e..f1e3132bb5b3a31f8651bf232eb4098856220eec 100755
--- a/tools/grit/grit/format/resource_map.py
+++ b/tools/grit/grit/format/resource_map.py
@@ -66,15 +66,17 @@ extern const size_t %(map_name)sSize;
 ''' % { 'map_name': GetMapName(root) }
 
 
-def _FormatSourceHeader(root):
+def _FormatSourceHeader(root, output_dir):
   '''Create the header of the C++ source file for the resource mapping.'''
   rc_header_file = None
   map_header_file = None
   for output in root.GetOutputFiles():
     if 'rc_header' == output.GetType():
-      rc_header_file = output.GetFilename()
+      rc_header_file = util.MakeRelativePath(output_dir,
+                                             output.GetOutputFilename())
     elif 'resource_map_header' == output.GetType():
-      map_header_file = output.GetFilename()
+      map_header_file = util.MakeRelativePath(output_dir,
+                                              output.GetOutputFilename())

[scottmg, 2017/03/03 19:29:57]

The change from GetFilename to GetOutputFilename was intentional? I couldn't
obviously see what the difference between the two was supposed to be.

[Nico, 2017/03/03 19:35:08]

Yes, it's intentional. If the grd file looks like

    <output filename="grit/login_resources_map.cc"
type="resource_file_map_source" />
    <output filename="grit/login_resources_map.h" type="resource_map_header" />

then GetFilename() returns "grit/login_resources_map.h"

GetOutputFilename() on the other hand checks if output_filename exists
(https://cs.chromium.org/chromium/src/tools/grit/grit/node/io.py?rcl=d80646f53...)
and the grit driver takes its -o flag and sets output_filename to join(-o-value,
path)
(https://cs.chromium.org/chromium/src/tools/grit/grit/tool/build.py?q=%5C-o+fi...),
so if the output goes to ui/login then GetOutputFilename() returns
ui/login/grit/login_resources_map.h.

output_dir for the _map file is ui/login/grit/, so the relpath is then just
login_resources_map.h. With GetFilename, the relpath from ui/login/grit to
grit/login_resources_map.h would be ../../../grit/login_resources_map.h which
wouldn't be good.

   if not rc_header_file or not map_header_file:
     raise Exception('resource_map_source output type requires '
         'resource_map_header and rc_header outputs')
@@ -108,7 +110,7 @@ const size_t %(map_name)sSize = arraysize(%(map_name)s);
 def _FormatSource(get_key, root, lang, output_dir):
   from grit.format import rc_header
   from grit.node import include, structure, message
-  yield _FormatSourceHeader(root)
+  yield _FormatSourceHeader(root, output_dir)
   tids = rc_header.GetIds(root)
   seen = set()
   active_descendants = [item for item in root.ActiveDescendants()]