GN: Use interface jars in the classpath to speed up compiling (a little)

build/config/android/internal_rules.gni

 # Copyright 2014 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/config.gni")
 import("//third_party/ijar/ijar.gni")
 
 assert(is_android)
 
 rebased_android_sdk = rebase_path(android_sdk, root_build_dir)
@@ skipping 395 matching lines @@
     }
   }
 }
 
 template("process_java_prebuilt") {
   set_sources_assignment_filter([])
   forward_variables_from(invoker, [ "testonly" ])
 
   _input_jar_path = invoker.input_jar_path
   _output_jar_path = invoker.output_jar_path
-  _jar_toc_path = _output_jar_path + ".TOC"
+  _output_ijar_path = get_path_info(_output_jar_path, "dir") + "/" +
+                      get_path_info(_output_jar_path, "name") + ".interface.jar"
 
   assert(invoker.build_config != "")
 
   if (defined(invoker.proguard_preprocess) && invoker.proguard_preprocess) {
     _proguard_jar_path = "//third_party/proguard/lib/proguard.jar"
     _proguard_config_path = invoker.proguard_config
     _build_config = invoker.build_config
     _rebased_build_config = rebase_path(_build_config, root_build_dir)
     _output_jar_target = "${target_name}__proguard_process"
     action(_output_jar_target) {
@@ skipping 43 matching lines @@
                              ])
       sources = [
         _input_jar_path,
       ]
       outputs = [
         _output_jar_path,
       ]
     }
   }
 
-  # TODO(agrieve): Change file extension to .ijar and use them in classpaths.
-  generate_interface_jar("${target_name}__jar_toc") {
+  generate_interface_jar("${target_name}__ijar") {
     input_jar = _output_jar_path
-    output_jar = _jar_toc_path
+    output_jar = _output_ijar_path
     deps = [
       ":$_output_jar_target",
     ]
   }
 
   group(target_name) {
     forward_variables_from(invoker, [ "visibility" ])
     public_deps = [
-      ":${target_name}__jar_toc",
+      ":${target_name}__ijar",
       ":$_output_jar_target",
     ]
   }
 }
 
 # Creates an unsigned .apk.
 #
 # Variables
 #   deps: Specifies the dependencies of this target.
 #   dex_path: Path to classes.dex file to include (optional).
@@ skipping 474 matching lines @@
     if (defined(invoker.main_class)) {
       data_deps += [ ":$binary_script_target_name" ]
     }
   }
 }
 
 # Compiles and jars a set of java files.
 #
 # Outputs:
 #  $jar_path.jar
-#  $jar_path.jar.TOC
+#  $jar_path.interface.jar
 #
 # Variables
 #   java_files: List of .java files to compile.
 #   java_deps: List of java dependencies. These should all have a .jar output
 #     at "${target_gen_dir}/${target_name}.jar.
 #   chromium_code: If true, enable extra warnings.
 #   srcjar_deps: List of srcjar dependencies. The .java files contained in the
 #     dependencies srcjar outputs will be compiled and added to the output jar.
 #   jar_path: Use this to explicitly set the output jar path. Defaults to
 #     "${target_gen_dir}/${target_name}.jar.
@@ skipping 78 matching lines @@
     ]
     sources = _java_files + _java_srcjars
     inputs = [
       _build_config,
     ]
 
     _rebased_java_srcjars = rebase_path(_java_srcjars, root_build_dir)
     _rebased_depfile = rebase_path(depfile, root_build_dir)
     args = [
       "--depfile=$_rebased_depfile",
+      "--use-ijars",
       "--classpath=@FileArg($_rebased_build_config:javac:classpath)",
       "--jar-path=$_rebased_jar_path",
       "--java-srcjars=$_rebased_java_srcjars",
       "--java-srcjars=@FileArg($_rebased_build_config:javac:srcjars)",
       "--jar-excluded-classes=$_jar_excluded_patterns",
     ]
     if (_supports_android) {
-      _rebased_android_sdk_jar = rebase_path(android_sdk_jar, root_build_dir)
-      args += [ "--bootclasspath=$_rebased_android_sdk_jar" ]
+      deps += [ "//build/android:android_ijar" ]
+      _android_sdk_ijar = "$root_out_dir/lib.java/android.interface.jar"
+      inputs += [ _android_sdk_ijar ]
+      _rebased_android_sdk_ijar = rebase_path(_android_sdk_ijar, root_build_dir)
+      args += [ "--bootclasspath=$_rebased_android_sdk_ijar" ]
     }
     foreach(e, _manifest_entries) {
       args += [ "--manifest-entry=" + e ]
     }
     if (_chromium_code) {
       args += [ "--chromium-code=1" ]
     }
     if (_enable_errorprone) {
       deps += [ "//third_party/errorprone:chromium_errorprone" ]
       args += [
@@ skipping 504 matching lines @@
     ]
     args = [
       "--depfile",
       rebase_path(depfile, root_build_dir),
       "--script-output-path",
       rebase_path(generated_script, root_build_dir),
     ]
     args += test_runner_args
   }
 }