Make _incremental targets work with emma_coverage=true

build/config/android/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("//base/android/linker/config.gni")
 import("//build/config/android/config.gni")
 import("//build/config/android/internal_rules.gni")
 import("//build/config/sanitizers/sanitizers.gni")
 import("//build/toolchain/toolchain.gni")
 import("//third_party/android_platform/config.gni")
@@ skipping 1432 matching lines @@
     deps = _native_libs_deps + _android_manifest_deps
     if (defined(invoker.deps)) {
       deps += invoker.deps
     }
 
     if (defined(invoker.alternative_locale_resource_dep)) {
       deps += [ invoker.alternative_locale_resource_dep ]
       has_alternative_locale_resource = true
     }
 
+    # Added emma to the target's classpath via its .build_config.
+    if (emma_coverage && !_emma_never_instrument) {
+      deps += [ "//third_party/android_tools:emma_device" ]
+    }
+
     proguard_enabled = _proguard_enabled
     if (_proguard_enabled) {
       proguard_info = "$_proguard_jar_path.info"
     }
 
     native_libs = _native_libs
   }
 
   _final_deps = []
 
@@ skipping 206 matching lines @@
 
     # All deps are already included in _dex_sources when proguard is used.
     if (!_proguard_enabled) {
       if (enable_multidex) {
         _dex_arg_key = "${_rebased_build_config}:dist_jar:dependency_jars"
       } else {
         _dex_arg_key = "${_rebased_build_config}:final_dex:dependency_dex_files"
       }
       args = [ "--inputs=@FileArg($_dex_arg_key)" ]
     }
-
-    if (emma_coverage && !_emma_never_instrument) {
-      no_locals = true
-      sources += [ "$android_sdk_root/tools/lib/emma_device.jar" ]
-    }
   }
 
   _native_libs_file_arg_dep = ":$build_config_target"
   _native_libs_file_arg = "@FileArg($_rebased_build_config:native:libraries)"
 
   if (_native_libs != [] && _enable_relocation_packing) {
     _prepare_native_target_name = "${_template_name}__prepare_native"
     _native_libs_dir = "$gen_dir/packed-libs"
     _native_libs_json = "$gen_dir/packed-libs/filelist.json"
     _rebased_native_libs_json = rebase_path(_native_libs_json, root_build_dir)
@@ skipping 722 matching lines @@
       "--target",
       rebase_path(invoker.target, root_build_dir),
       "--output-directory",
       rebase_path(root_out_dir, root_build_dir),
     ]
     if (defined(invoker.flag_name)) {
       args += [ "--flag-name=${invoker.flag_name}" ]
     }
   }
 }