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

tools/gn/copy_target_generator.h

Index: tools/gn/copy_target_generator.h
diff --git a/tools/gn/copy_target_generator.h b/tools/gn/copy_target_generator.h
index 81fbb69e8e74ef931faf6699bb0e42c8038a8601..65f684632dfb451b91352378e3bcd83a2fb35669 100644
--- a/tools/gn/copy_target_generator.h
+++ b/tools/gn/copy_target_generator.h
@@ -6,6 +6,7 @@
 #define TOOLS_GN_COPY_TARGET_GENERATOR_H_
 
 #include "base/macros.h"
+#include "tools/gn/target.h"
 #include "tools/gn/target_generator.h"
 
 // Populates a Target with the values from a copy rule.
@@ -14,6 +15,7 @@ class CopyTargetGenerator : public TargetGenerator {
   CopyTargetGenerator(Target* target,
                       Scope* scope,
                       const FunctionCallNode* function_call,
+                      Target::OutputType output_type,
                       Err* err);
   ~CopyTargetGenerator() override;
 
@@ -23,6 +25,8 @@ class CopyTargetGenerator : public TargetGenerator {
  private:
   void FillDestDir();
 
+  Target::OutputType output_type_;
+
   DISALLOW_COPY_AND_ASSIGN(CopyTargetGenerator);
 };