Port custom_tabs_client from GYP to GN

build/config/android/rules.gni

Index: build/config/android/rules.gni
diff --git a/build/config/android/rules.gni b/build/config/android/rules.gni
index dee611624e988b146cb2f20d741a4b8c73b322b2..bdc3373b0a909aa72238a10ad3b5b6e7f040ebd4 100644
--- a/build/config/android/rules.gni
+++ b/build/config/android/rules.gni
@@ -1105,6 +1105,7 @@ template("android_java_prebuilt") {
 # Variables
 #   android_manifest: Path to AndroidManifest.xml.
 #   android_manifest_dep: Target that generates AndroidManifest (if applicable)
+#   chromium_code: If true, extra analysis warning/errors will be enabled.
 #   data_deps: List of dependencies needed at runtime. These will be built but
 #     won't change the generated .apk in any way (in fact they may be built
 #     after the .apk is).
@@ -1376,13 +1377,21 @@ template("android_apk") {
   java_target = "${_template_name}__java"
   java_library_impl(java_target) {
     forward_variables_from(invoker, [ "run_findbugs" ])
+    assert(run_findbugs || true)  # Mark as used.

[agrieve, 2015/09/28 14:52:49]

I think if you move this into java_library_impl, you can mark:

https://code.google.com/p/chromium/issues/detail?id=536092

as fixed :)

+
     supports_android = true
     requires_android = true
     override_build_config = _build_config
     deps = _android_manifest_deps + [ ":$build_config_target" ]
 
     android_manifest = _android_manifest
+    assert(android_manifest != "")  # Mark as used.

[agrieve, 2015/09/28 14:52:49]

I think this should also be moved to within java_library_impl since it's the one
not properly marking it as used.

+
     chromium_code = true
+    if (defined(invoker.chromium_code)) {
+      chromium_code = invoker.chromium_code
+    }
+
     if (defined(invoker.java_files)) {
       java_files = invoker.java_files
     } else if (defined(invoker.DEPRECATED_java_in_dir)) {