Ship dart2js output for dev_compiler/web in the sdk.

utils/dartdevc/BUILD.gn

Index: utils/dartdevc/BUILD.gn
diff --git a/utils/dartdevc/BUILD.gn b/utils/dartdevc/BUILD.gn
index b67300a461510d0adae125fbc7840e20339d2161..094cd76a717df8cc390d2d9a086c295bd1b20595 100644
--- a/utils/dartdevc/BUILD.gn
+++ b/utils/dartdevc/BUILD.gn
@@ -23,3 +23,58 @@ application_snapshot("dartdevc") {
                          rebase_path("../../pkg/dev_compiler/bin") ],
                        "list lines")
 }
+
+sdk_lib_files = exec_script(
+    "../../tools/list_dart_files.py",
+    [ "absolute", rebase_path("../../sdk/lib") ],
+    "list lines")
+
+compiler_files = exec_script(
+    "../../tools/list_dart_files.py",
+    [ "absolute", rebase_path("../../pkg/compiler") ],
+    "list lines")
+
+dev_compiler_files = exec_script(
+    "../../tools/list_dart_files.py",
+    [ "absolute", rebase_path("../../pkg/dev_compiler") ],
+    "list lines")
+
+template("dart2js_compile") {
+  assert(defined(invoker.main), "Must specify the main file")
+  main = invoker.main
+  assert(defined(invoker.out), "Must specify the out file")
+  out = invoker.out
+  abs_main = rebase_path(main)
+  abs_output = rebase_path(out)
+
+  compiled_action(target_name) {
+    tool = "../../runtime/bin:dart"
+    inputs = sdk_lib_files + compiler_files + dev_compiler_files
+    outputs = [
+      out,
+    ]
+
+    dot_packages = rebase_path("../../.packages")
+    compiler =
+        rebase_path("../../pkg/compiler/lib/src/dart2js.dart")
+
+    args = [
+      "--packages=$dot_packages",
+      compiler,
+      "--packages=$dot_packages",
+      "$abs_main",
+      "-m",
+      "-o$abs_output",
+    ]
+  }
+}
+
+dart2js_compile("dartdevc_web") {
+  main = rebase_path("../../pkg/dev_compiler/web/main.dart")
+  out = "$root_out_dir/dev_compiler/build/web/ddc_web_compiler.js"
+}
+
+dart2js_compile("stack_trace_mapper") {
+  main = rebase_path("../../pkg/dev_compiler/web/stack_trace_mapper.dart")
+  out = "$root_out_dir/dev_compiler/build/web/dart_stack_trace_mapper.js"
+}