Hook up LeakCanary to ChromePublic.apk (behind a GN arg)

chrome/android/chrome_public_apk_tmpl.gni

 # Copyright 2015 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/android/rules.gni")
+import("//chrome/common/features.gni")
+import("//third_party/leakcanary/config.gni")
+import("channel.gni")
 
 declare_args() {
   # Whether chrome_public_apk should use the crazy linker.
   chrome_public_apk_use_chromium_linker = true
 
   # Whether chrome_public_apk should use the relocation packer.
   chrome_public_apk_use_relocation_packer = true
 
   # Whether native libraries should be loaded from within the apk.
   chrome_public_apk_load_library_from_apk = true
 }
 
+default_chrome_public_jinja_variables = [
+  "channel=$android_channel",
+  "enable_leakcanary=$enable_leakcanary",
+]
+if (enable_configuration_policy) {
+  default_chrome_public_jinja_variables += [ "configuration_policy=1" ]
+} else {
+  default_chrome_public_jinja_variables += [ "configuration_policy=0" ]
+}
+
 # GYP: //chrome/android/chrome_apk.gypi
 template("chrome_public_apk_tmpl") {
   android_apk(target_name) {
     forward_variables_from(invoker, "*")
     _native_lib_file =
         rebase_path("$root_gen_dir/CHROME_VERSION.json", root_out_dir)
     native_lib_version_arg = "@FileArg($_native_lib_file:full-quoted)"
 
     if (is_debug) {
       enable_multidex = true
@@ skipping 13 matching lines @@
         use_chromium_linker = chrome_public_apk_use_chromium_linker
       }
 
       # TODO: Enable packed relocations for x64. See: b/20532404
       if (current_cpu != "x64") {
         enable_relocation_packing = chrome_public_apk_use_relocation_packer
       }
     }
   }
 }