[Cronet] Build static libcronet.a for iOS with complete dependencies.

components/cronet/ios/cronet_consumer/BUILD.gn

 # Copyright 2016 The Chromium Authors. All rights reserved.
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
 import("//build/config/ios/rules.gni")
+import("//ios/features.gni")
 
-ios_app_bundle("cronet_consumer") {
-  info_plist = "cronet-consumer-Info.plist"
+template("cronet_consumer_template") {
+  _target_name = target_name
 
+  ios_app_bundle(_target_name) {
+    info_plist = "cronet-consumer-Info.plist"
+
+    deps = [
+      "//base:base",
+    ]
+
+    deps += invoker.deps
+
+    sources = [
+      "cronet_consumer_app_delegate.h",
+      "cronet_consumer_app_delegate.mm",
+      "cronet_consumer_view_controller.h",
+      "cronet_consumer_view_controller.m",
+      "main.mm",
+    ]
+
+    forward_variables_from(invoker,
+                           [
+                             "bundle_deps",
+                             "cflags",
+                             "ldflags",
+                           ])
+
+    configs += [ "//build/config/compiler:enable_arc" ]
+  }
+}
+
+cronet_consumer_template("cronet_consumer") {
   deps = [
-    "//base:base",
     "//components/cronet/ios:cronet_framework+link",
+  ]
+  bundle_deps = [ "//components/cronet/ios:cronet_framework+bundle" ]
+}
 
-    # All shared libraries must have the sanitizer deps to properly link in
-    # asan mode (this target will be empty in other cases).
-    "//build/config:exe_and_shlib_deps",
-  ]
+# TODO(mef): Building "cronet_consumer_static" app with additional_target_cpus
+# causes "cronet_static_framework" to build lipo_binary("libcronet") for
+# duplicate architecture (e.g. arm64+arm64) and breaks the build.
+if (!defined(additional_target_cpus)) {
+  cronet_consumer_template("cronet_consumer_static") {
+    deps = [
+      "//components/cronet/ios:cronet_static_framework",
+    ]
 
-  sources = [
-    "cronet_consumer_app_delegate.h",
-    "cronet_consumer_app_delegate.mm",
-    "cronet_consumer_view_controller.h",
-    "cronet_consumer_view_controller.m",
-    "main.mm",
-  ]
+    cflags = [

[mef, 2017/06/02 16:26:17]

What's a better way to add $root_out_dir/Static to framework search path, so it
would find 'Cronet.framework' ?

+      "-F",
+      "Static",
+    ]
 
-  bundle_deps = [ "//components/cronet/ios:cronet_framework+bundle" ]
-
-  configs += [ "//build/config/compiler:enable_arc" ]
+    ldflags = [
+      "-F",
+      "Static",
+    ]
+  }
 }