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

tools/gn/copy_target_generator.cc

Index: tools/gn/copy_target_generator.cc
diff --git a/tools/gn/copy_target_generator.cc b/tools/gn/copy_target_generator.cc
index 994011e824e614e5bdb5660d1a501fe2af7d5c64..24ca1fe65cf78fdf6e0a5722a5f589628d1234cf 100644
--- a/tools/gn/copy_target_generator.cc
+++ b/tools/gn/copy_target_generator.cc
@@ -13,26 +13,37 @@
 CopyTargetGenerator::CopyTargetGenerator(Target* target,
                                          Scope* scope,
                                          const FunctionCallNode* function_call,
+                                         Target::OutputType output_type,
                                          Err* err)
-    : TargetGenerator(target, scope, function_call, err) {
-}
+    : TargetGenerator(target, scope, function_call, err),
+      output_type_(output_type) {}
 
 CopyTargetGenerator::~CopyTargetGenerator() {
 }
 
 void CopyTargetGenerator::DoRun() {
-  target_->set_output_type(Target::COPY_FILES);
+  target_->set_output_type(output_type_);
+
+  if (output_type_ == Target::COPY_FILES) {
+    if (!FillSources())
+      return;
+
+    if (target_->sources().empty()) {
+      *err_ = Err(
+          function_call_, "Empty sources for copy command.",
+          "You have to specify at least one file to copy in the \"sources\".");
+      return;
+    }
+  }
+
+  if (output_type_ == Target::COPY_BUNDLE_DATA) {
+    if (!FillBundleDataFilter())
+      return;
+  }
 
-  if (!FillSources())
-    return;
   if (!FillOutputs(true))
     return;
 
-  if (target_->sources().empty()) {
-    *err_ = Err(function_call_, "Empty sources for copy command.",
-        "You have to specify at least one file to copy in the \"sources\".");
-    return;
-  }
   if (target_->action_values().outputs().list().size() != 1) {
     *err_ = Err(function_call_, "Copy command must have exactly one output.",
         "You must specify exactly one value in the \"outputs\" array for the "