Add support for Mac/iOS application bundles to GN tool.

tools/gn/target.h

Index: tools/gn/target.h
diff --git a/tools/gn/target.h b/tools/gn/target.h
index eff4d150d53e5dd3a7856926c3ab0ed7d6925f3a..599185fe25bc778240201aa5c367caa456cd2600 100644
--- a/tools/gn/target.h
+++ b/tools/gn/target.h
@@ -40,6 +40,7 @@ class Target : public Item {
     STATIC_LIBRARY,
     SOURCE_SET,
     COPY_FILES,
+    COPY_BUNDLE_DATA,
     ACTION,
     ACTION_FOREACH,
   };
@@ -134,7 +135,8 @@ class Target : public Item {
   bool hard_dep() const {
     return output_type_ == ACTION ||
            output_type_ == ACTION_FOREACH ||
-           output_type_ == COPY_FILES;
+           output_type_ == COPY_FILES ||
+           output_type_ == COPY_BUNDLE_DATA;

[brettw, 2016/01/20 22:23:17]

Are you sure you need this?

The COPY_FILES rule is here because it may copy a header file that is required
to compile a source file. Unless the copy rule is executed first, compilation
may fail.

But I don't think compilation steps will take bundle data as input. I believe
only an script will, and an action will always require its inputs to be
up-to-date before doing anything.

The reason not to do this is that the COPY_BUNDLE_DATA step will require that
all dependencies be up-to-date, and marking it as hard requires it be done
before any dependencies are compiled, so this will serialize a significant part
of the build.

If not having this gives a problem, we should understand exactly what the issue
is, maybe there's a less destructive way to express what we need.

[sdefresne, 2016/01/21 22:00:56]

Good point. Removed.

   }
 
   // Returns the iterator range which can be used in range-based for loops