[Mojo Lite] Remove externs generators and use for-compile generators everywhere.

This CL removes the Mojo Lite externs generators and compiles all WebUIs
with the for-compile targets instead.

Structurally, all Mojo types are now Closure record typedefs, and their
generated business logic is underneath a Spec object to prevent the name
collisions that were happening in the original implementation.

All goog.requires have also been dropped, and goog.provides are now
per interface/struct/enum.

This CL paves the way for generating single file Closure compiled blobs
that have all the Mojo bindings for a single WebUI.

TBR=kinuko@chromium.org

Bug: 914149
Change-Id: I8866fa9eaa707b2db42369e695ed0a51c373c6b6
Reviewed-on: https://chromium-review.googlesource.com/c/1476886
Commit-Queue: calamity <calamity@chromium.org>
Reviewed-by: Ken Rockot <rockot@google.com>
Cr-Commit-Position: refs/heads/master@{#634527}

chrome/browser/resources/app_management/BUILD.gn

@@ -38,7 +38,7 @@ if (!is_android) {
 
   js_library("actions") {
     deps = [
-      "//chrome/browser/ui/webui/app_management:mojo_bindings_js_externs",
+      "//chrome/browser/ui/webui/app_management:mojo_bindings_js_library_for_compile",
       "//ui/webui/resources/js:cr",
     ]
   }
@@ -67,7 +67,7 @@ if (!is_android) {
       ":store_client",
       ":types",
       ":util",
-      "//chrome/browser/ui/webui/app_management:mojo_bindings_js_externs",
+      "//chrome/browser/ui/webui/app_management:mojo_bindings_js_library_for_compile",
     ]
   }
 
@@ -93,7 +93,7 @@ if (!is_android) {
   js_library("browser_proxy") {
     deps = [
       ":fake_page_handler",
-      "//chrome/browser/ui/webui/app_management:mojo_bindings_js_externs",
+      "//chrome/browser/ui/webui/app_management:mojo_bindings_js_library_for_compile",
       "//ui/webui/resources/js:cr",
     ]
   }
@@ -125,7 +125,7 @@ if (!is_android) {
       ":constants",
       ":types",
       ":util",
-      "//chrome/browser/ui/webui/app_management:mojo_bindings_js_externs",
+      "//chrome/browser/ui/webui/app_management:mojo_bindings_js_library_for_compile",
       "//ui/webui/resources/js:cr",
     ]
   }
@@ -238,7 +238,7 @@ if (!is_android) {
 
   js_library("types") {
     deps = [
-      "//chrome/browser/ui/webui/app_management:mojo_bindings_js_externs",
+      "//chrome/browser/ui/webui/app_management:mojo_bindings_js_library_for_compile",
     ]
   }
 

chrome/browser/resources/app_management/metadata_view.js

@@ -57,7 +57,7 @@ Polymer({
     }
 
     app_management.BrowserProxy.getInstance().handler.setPinned(
-        this.app_.id, newPinnedValue);
+        this.app_.id, assert(newPinnedValue));
   },
 
   /**

chrome/browser/resources/app_management/permission_toggle.js

@@ -82,7 +82,7 @@ Polymer({
 
     return app_management.util.createPermission(
         app_management.util.permissionTypeHandle(app, permissionType),
-        PermissionValueType.kBool, newPermissionValue);
+        PermissionValueType.kBool, assert(newPermissionValue));
   },
 
   /**
@@ -114,6 +114,6 @@ Polymer({
 
     return app_management.util.createPermission(
         app_management.util.permissionTypeHandle(app, permissionType),
-        PermissionValueType.kTriState, newPermissionValue);
+        PermissionValueType.kTriState, assert(newPermissionValue));
   },
 });

chrome/browser/resources/bluetooth_internals/BUILD.gn

@@ -31,7 +31,7 @@ js_library("bluetooth_internals") {
   ]
 
   deps = [
-    "//chrome/browser/ui/webui/bluetooth_internals:mojo_bindings_js_externs",
+    "//chrome/browser/ui/webui/bluetooth_internals:mojo_bindings_js_library_for_compile",
     "//ui/webui/resources/js:cr",
     "//ui/webui/resources/js:util",
     "//ui/webui/resources/js/cr/ui:array_data_model",

chrome/browser/resources/discards/BUILD.gn

@@ -31,7 +31,7 @@ js_library("database_tab") {
   deps = [
     ":discards",
     ":sorted_table_behavior",
-    "//chrome/browser/ui/webui/discards:mojo_bindings_js_externs",
+    "//chrome/browser/ui/webui/discards:mojo_bindings_js_library_for_compile",
     "//ui/webui/resources/js:assert",
     "//ui/webui/resources/js:cr",
   ]
@@ -41,7 +41,7 @@ js_library("discards_tab") {
   deps = [
     ":discards",
     ":sorted_table_behavior",
-    "//chrome/browser/ui/webui/discards:mojo_bindings_js_externs",
+    "//chrome/browser/ui/webui/discards:mojo_bindings_js_library_for_compile",
     "//ui/webui/resources/js:assert",
     "//ui/webui/resources/js:icon",
     "//ui/webui/resources/js:util",
@@ -50,8 +50,8 @@ js_library("discards_tab") {
 
 js_library("graph_tab") {
   deps = [
-    "//chrome/browser/ui/webui/discards:mojo_bindings_js_externs",
-    "//services/resource_coordinator/public/mojom:mojom_js_externs",
+    "//chrome/browser/ui/webui/discards:mojo_bindings_js_library_for_compile",
+    "//services/resource_coordinator/public/mojom:mojom_js_library_for_compile",
     "//ui/webui/resources/js:assert",
     "//ui/webui/resources/js:cr",
   ]
@@ -59,7 +59,7 @@ js_library("graph_tab") {
 
 js_library("graph_doc") {
   deps = [
-    "//services/resource_coordinator/public/mojom:mojom_js_externs",
+    "//services/resource_coordinator/public/mojom:mojom_js_library_for_compile",
   ]
 
   externs_list = [ "../../../../third_party/d3/src/externs.js" ]

chrome/browser/resources/downloads/BUILD.gn

@@ -34,7 +34,7 @@ js_type_check("closure_compile") {
 
 js_library("browser_proxy") {
   deps = [
-    "//chrome/browser/ui/webui/downloads:mojo_bindings_js_externs",
+    "//chrome/browser/ui/webui/downloads:mojo_bindings_js_library_for_compile",
     "//ui/webui/resources/js:cr",
   ]
   externs_list = [ "externs.js" ]

chrome/browser/resources/engagement/BUILD.gn

@@ -12,7 +12,7 @@ js_type_check("closure_compile") {
 
 js_library("site_engagement") {
   deps = [
-    "//chrome/browser/engagement:mojo_bindings_js_externs",
+    "//chrome/browser/engagement:mojo_bindings_js_library_for_compile",
     "//ui/webui/resources/js:assert",
     "//ui/webui/resources/js:util",
   ]

chrome/browser/resources/omnibox/BUILD.gn

@@ -12,16 +12,10 @@ js_type_check("closure_compile") {
 
 js_library("omnibox") {
   deps = [
-    "//ui/webui/resources/js:util",
     ":omnibox_element",
     ":omnibox_input",
     ":omnibox_output",
-  ]
-  extra_deps = [ "//chrome/browser/ui/webui/omnibox:mojo_bindings_js" ]
-  externs_list = [
-    "$root_gen_dir/chrome/browser/ui/webui/omnibox/omnibox.mojom-lite.externs.js",
-    "$externs_path/mojo.js",
-    "$externs_path/pending.js",
+    "//chrome/browser/ui/webui/omnibox:mojo_bindings_js_library_for_compile",
   ]
 }
 
@@ -32,4 +26,7 @@ js_library("omnibox_input") {
 }
 
 js_library("omnibox_output") {
+  deps = [
+    "//ui/webui/resources/js:util",
+  ]
 }

chrome/browser/resources/settings/bluetooth_page/BUILD.gn

@@ -61,6 +61,6 @@ js_library("bluetooth_device_list_item") {
 js_library("bluetooth_system_on_extensions") {
   sources = []
   deps = [
-    "//services/device/public/mojom:mojom_js_externs",
+    "//services/device/public/mojom:mojom_js_library_for_compile",
   ]
 }

chrome/browser/resources/usb_internals/BUILD.gn

@@ -16,7 +16,7 @@ js_library("usb_internals") {
   ]
 
   deps = [
-    "//chrome/browser/ui/webui/usb_internals:mojo_bindings_js_externs",
+    "//chrome/browser/ui/webui/usb_internals:mojo_bindings_js_library_for_compile",
     "//ui/webui/resources/js:cr",
     "//ui/webui/resources/js:util",
     "//ui/webui/resources/js/cr/ui:tabs",

content/browser/resources/process/BUILD.gn

@@ -12,7 +12,7 @@ js_type_check("closure_compile") {
 
 js_library("process_internals") {
   deps = [
-    "//content/browser/process_internals:mojo_bindings_js_externs",
+    "//content/browser/process_internals:mojo_bindings_js_library_for_compile",
     "//ui/webui/resources/js:assert",
     "//ui/webui/resources/js:util",
     "//ui/webui/resources/js/cr/ui:tree",

mojo/public/js/BUILD.gn

@@ -60,14 +60,14 @@ bindings_lite_sources = [
 
 bindings_lite_compiled_file = "$target_gen_dir/mojo_bindings_lite.js"
 
-if (enable_mojom_closure_compile) {
-  js_library("bindings_lite_sources") {
-    sources = [ "compile_preamble.js" ] + bindings_lite_sources
-    deps = [
-      "//mojo/public/interfaces/bindings:bindings_js_library_for_compile",
-    ]
-  }
+js_library("bindings_lite_sources") {
+  sources = [ "compile_preamble.js" ] + bindings_lite_sources
+  deps = [
+    "//mojo/public/interfaces/bindings:bindings_js_library_for_compile",
+  ]
+}
 
+if (enable_mojom_closure_compile || closure_compile) {
   js_binary("bindings_lite") {
     outputs = [
       bindings_lite_compiled_file,

mojo/public/js/interface_support.js

@@ -3,7 +3,8 @@
 // found in the LICENSE file.
 'use strict';
 
-goog.require('mojo.interfaceControl');
+goog.require('mojo.interfaceControl.kRunMessageId');
+goog.require('mojo.interfaceControl.RunResponseMessageParamsSpec');
 goog.require('mojo.internal');
 
 goog.provide('mojo.internal.interfaceSupport');
@@ -27,7 +28,7 @@ mojo.internal.interfaceSupport.ControlMessageHandler = class {
       mojo.internal.serializeAndSendMessage(
           this.handle_, mojo.interfaceControl.kRunMessageId, requestId,
           mojo.internal.kMessageFlagExpectsResponse,
-          mojo.interfaceControl.RunMessageParams.$, {'input': input});
+          mojo.interfaceControl.RunMessageParamsSpec.$, {'input': input});
       this.pendingFlushResolvers_.set(requestId, resolve);
     });
   }
@@ -47,12 +48,13 @@ mojo.internal.interfaceSupport.ControlMessageHandler = class {
 
   handleRunRequest_(requestId, decoder) {
     const input = decoder.decodeStructInline(
-        mojo.interfaceControl.RunMessageParams.$.$.structSpec)['input'];
+        mojo.interfaceControl.RunMessageParamsSpec.$.$.structSpec)['input'];
     if (input.hasOwnProperty('flushForTesting')) {
       mojo.internal.serializeAndSendMessage(
           this.handle_, mojo.interfaceControl.kRunMessageId, requestId,
           mojo.internal.kMessageFlagIsResponse,
-          mojo.interfaceControl.RunResponseMessageParams.$, {'output': null});
+          mojo.interfaceControl.RunResponseMessageParamsSpec.$,
+          {'output': null});
       return true;
     }
 

mojo/public/js/lib/codec.js

@@ -349,7 +349,7 @@
 
     if (cls === PackedBool) {
       var byte = 0;
-      for (i = 0; i < numberOfElements; ++i) {
+      for (let i = 0; i < numberOfElements; ++i) {
         if (val[i])
           byte |= (1 << i % 8);
         if (i % 8 === 7 || i == numberOfElements - 1) {

mojo/public/js/lib/control_message_proxy.js

@@ -54,7 +54,7 @@
   * Accepts the response message from the receiver and decodes the message
   * struct to RunResponseMessageParams.
   *
-  * @param  {Router} receiver.
+  * @param  {Router} receiver
   * @param  {RunMessageParams} runMessageParams to be sent via a message.
   * @return {Promise} that resolves to a RunResponseMessageParams.
   */

mojo/public/tools/bindings/BUILD.gn

@@ -70,14 +70,10 @@ action("precompile_templates") {
     "$mojom_generator_root/generators/js_templates/interface_definition.tmpl",
     "$mojom_generator_root/generators/js_templates/lite/enum_definition.tmpl",
     "$mojom_generator_root/generators/js_templates/lite/interface_definition.tmpl",
-    "$mojom_generator_root/generators/js_templates/lite/interface_externs.tmpl",
-    "$mojom_generator_root/generators/js_templates/lite/module.externs.tmpl",
     "$mojom_generator_root/generators/js_templates/lite/module_definition.tmpl",
     "$mojom_generator_root/generators/js_templates/lite/mojom-lite.js.tmpl",
     "$mojom_generator_root/generators/js_templates/lite/struct_definition.tmpl",
-    "$mojom_generator_root/generators/js_templates/lite/struct_externs.tmpl",
     "$mojom_generator_root/generators/js_templates/lite/union_definition.tmpl",
-    "$mojom_generator_root/generators/js_templates/lite/union_externs.tmpl",
     "$mojom_generator_root/generators/js_templates/module.amd.tmpl",
     "$mojom_generator_root/generators/js_templates/module_definition.tmpl",
     "$mojom_generator_root/generators/js_templates/struct_definition.tmpl",

mojo/public/tools/bindings/generators/js_templates/lite/enum_definition.tmpl

-{%- macro enum_def(enum_name, enum) -%}
+{%- macro enum_def(enum_spec_parent, enum_parent, enum) -%}
 {# TODO: Less generic enum annotations would be nice. We do it this way because
    the bindings generator is still too stupid to generate the right integral
    constants directly. #}
+{%  if generate_closure_exports -%}
+goog.provide('{{enum_spec_parent}}.{{enum.name}}Spec');
+{%- endif %}
 /**
- * @const {!Object}
+ * @const { {$: !mojo.internal.MojomType} }
  * @export
  */
-{{enum_name}} = { $: mojo.internal.Enum() };
+{{enum_spec_parent}}.{{enum.name}}Spec = { $: mojo.internal.Enum() };
+
+/**
+ * @enum {number}
+ * @export
+ */
+{{enum_parent}}.{{enum.name}} = {
+  {# Set up the enum here, but fill out the values later. #}
 {%-   for field in enum.fields %}
-{%-     if field.value %}
-{{enum_name}}.{{field.name}} = {{field.value|expression_to_text_lite}};
-{%-     elif loop.first %}
-{{enum_name}}.{{field.name}} = 0;
-{%-     else %}
-{{enum_name}}.{{field.name}} = {{enum_name}}.{{enum.fields[loop.index0 - 1].name}} + 1;
-{%-     endif %}
+  {{field.name}}: 0,
 {%-   endfor %}
 {%-   if enum.min_value is not none %}
-{{enum_name}}.MIN_VALUE = {{enum.min_value}};
+  MIN_VALUE: {{enum.min_value}},
 {%-   endif %}
 {%-   if enum.max_value is not none %}
-{{enum_name}}.MAX_VALUE = {{enum.max_value}};
+  MAX_VALUE: {{enum.max_value}},
 {%-   endif %}
+};
+{%-   for field in enum.fields %}
+{# Suppress type checks since we're assigning number into an enum. #}
+/** @suppress {checkTypes} */
+{%-     if field.value %}
+{{enum_parent}}.{{enum.name}}.{{field.name}} = {{field.value|expression_to_text_lite}};
+{%-     elif loop.first %}
+{{enum_parent}}.{{enum.name}}.{{field.name}} = 0;
+{%-     else %}
+{{enum_parent}}.{{enum.name}}.{{field.name}} = {{enum_parent}}.{{enum.name}}.{{enum.fields[loop.index0 - 1].name}} + 1;
+{%-     endif %}
+{%-   endfor %}
 
 {%- endmacro %}

mojo/public/tools/bindings/generators/js_templates/lite/interface_definition.tmpl

+{% macro generateMethodAnnotation(method) %}
+  /**
+{%-   for param in method.parameters %}
+   * @param { {{param.kind|lite_closure_type_with_nullability}} } {{param.name|sanitize_identifier}}
+{%-   endfor -%}
+{%-   if method.response_parameters != None %}
+{%-     if method.response_parameters|length == 0 %}
+   * @return {Promise}
+{%-     else %}
+   * @return {Promise<{
+{%-       for response_parameter in method.response_parameters %}
+        {{response_parameter.name}}: {{response_parameter.kind|lite_closure_type_with_nullability}},
+{%-       endfor %}
+   *  }>}
+{%-     endif %}
+{%-   endif %}
+   */
+{% endmacro %}
+
 /** @export */
 {{module.namespace}}.{{interface.name}}Request = class {
   /** @param {!MojoHandle} handle */
@@ -11,14 +30,7 @@
 /** @interface */
 {{module.namespace}}.{{interface.name}}Interface = class {
 {%-  for method in interface.methods %}
-  /**
-{%-   for param in method.parameters %}
-   * @param { {{param.kind|lite_closure_param_type}} } {{param.name|sanitize_identifier}}
-{%-   endfor -%}
-{%-   if method.response_parameters != None %}
-   * @return {Promise}
-{%-   endif %}
-   */
+  {{generateMethodAnnotation(method)}}
   {{method.name}}(
 {%-   for param in method.parameters -%}
 {{param.name|sanitize_identifier}}{% if not loop.last %}, {% endif %}
@@ -28,7 +40,10 @@
 };
 {%- endif %}
 
-/** @implements { {{module.namespace}}.{{interface.name}}Interface } */
+/**
+ * @export
+ * @implements { {{module.namespace}}.{{interface.name}}Interface }
+ */
 {{module.namespace}}.{{interface.name}}Proxy = class {
   /** @param {MojoHandle=} opt_handle */
   constructor(opt_handle) {
@@ -41,7 +56,7 @@
           opt_handle);
 
     /**
-     * @public {!mojo.internal.interfaceSupport.InterfaceProxyBaseWrapper<!{{module.namespace}}.{{interface.name}}Request>>
+     * @public {!mojo.internal.interfaceSupport.InterfaceProxyBaseWrapper<!{{module.namespace}}.{{interface.name}}Request>}
      */
     this.$ = new mojo.internal.interfaceSupport.InterfaceProxyBaseWrapper(this.proxy);
 
@@ -53,15 +68,7 @@
 {%-   set interface_message_id =
           interface.mojom_name ~ "_" ~ method.mojom_name %}
 
-  /**
-{%-   for param in method.parameters %}
-   * @param { {{param.kind|lite_closure_param_type}} } {{param.name|sanitize_identifier}}
-{%-   endfor -%}
-{%-   if method.response_parameters != None %}
-   * @return {Promise}
-{%-   endif %}
-   * @export
-   */
+  {{generateMethodAnnotation(method)}}
   {{method.name}}(
 {%- for param in method.parameters %}
       {{param.name}}{%- if not loop.last %},{% endif %}
@@ -72,9 +79,9 @@
     this.proxy.sendMessage(
 {%- endif %}
         {{method.ordinal}},
-        {{module.namespace}}.{{interface_message_id}}_Params.$,
+        {{module.namespace}}.{{interface_message_id}}_ParamsSpec.$,
 {%-   if method.response_parameters != None %}
-        {{module.namespace}}.{{interface_message_id}}_ResponseParams.$,
+        {{module.namespace}}.{{interface_message_id}}_ResponseParamsSpec.$,
 {%-   else %}
         null,
 {%-   endif %}
@@ -105,9 +112,9 @@
           interface.mojom_name ~ "_" ~ method.mojom_name %}
     this.target_.registerHandler(
         {{method.ordinal}},
-        {{module.namespace}}.{{interface_message_id}}_Params.$,
+        {{module.namespace}}.{{interface_message_id}}_ParamsSpec.$,
 {%-   if method.response_parameters != None %}
-        {{module.namespace}}.{{interface_message_id}}_ResponseParams.$,
+        {{module.namespace}}.{{interface_message_id}}_ResponseParamsSpec.$,
 {%-   else %}
         null,
 {%-   endif %}
@@ -156,9 +163,10 @@
 };
 
 {#--- Enums #}
-{% from "lite/enum_definition.tmpl" import enum_def %}
+{% from "lite/enum_definition.tmpl" import enum_def with context %}
 {%- for enum in interface.enums %}
-{{ enum_def("%s.%s.%s"|format(module.namespace, interface.name, enum.name),
+{{ enum_def("%s.%sSpec"|format(module.namespace, interface.name),
+            "%s.%s"|format(module.namespace, interface.name),
             enum) }}
 {%-  endfor %}
 
@@ -184,15 +192,18 @@
 {%  for method in interface.methods %}
 {%-   set interface_message_id =
           interface.mojom_name ~ "_" ~ method.mojom_name %}
-    /** @public {!mojo.internal.interfaceSupport.InterfaceCallbackTarget} */
+    /**
+     * @export {!mojo.internal.interfaceSupport.InterfaceCallbackTarget}
+     */
     this.{{method.name}} =
         new mojo.internal.interfaceSupport.InterfaceCallbackTarget(
             this.router_);
+
     this.target_.registerHandler(
         {{method.ordinal}},
-        {{module.namespace}}.{{interface_message_id}}_Params.$,
+        {{module.namespace}}.{{interface_message_id}}_ParamsSpec.$,
 {%-   if method.response_parameters != None %}
-        {{module.namespace}}.{{interface_message_id}}_ResponseParams.$,
+        {{module.namespace}}.{{interface_message_id}}_ResponseParamsSpec.$,
         this.{{method.name}}.createTargetHandler(true /* expectsResponse */));
 {%-   else %}
         null,

mojo/public/tools/bindings/generators/js_templates/lite/interface_externs.tmpl

-{# Note that goog.provide is understood by the Closure Compiler even if the
-   Closure base library is unavailable. See https://crbug.com/898692 #}
-goog.provide('{{module.namespace}}.{{interface.name}}');
-goog.provide('{{module.namespace}}.{{interface.name}}Interface');
-goog.provide('{{module.namespace}}.{{interface.name}}Request');
-goog.provide('{{module.namespace}}.{{interface.name}}Proxy');
-goog.provide('{{module.namespace}}.{{interface.name}}CallbackRouter');
-
-{% macro generateInterfaceClassBody() -%}
-{%-  for method in interface.methods %}
-  /**
-{%-   for parameter in method.parameters %}
-   * @param { {{parameter.kind|lite_closure_type_with_nullability}} } {{parameter.name|sanitize_identifier}}
-{%-   endfor -%}
-{%-   if method.response_parameters != None %}
-{%-     if method.response_parameters|length == 0 %}
-   * @return {Promise}
-{%-     else %}
-   * @return {Promise<{
-{%-       for response_parameter in method.response_parameters %}
-        {{response_parameter.name}}: {{response_parameter.kind|lite_closure_type_with_nullability}},
-{%-       endfor %}
-   *  }>}
-{%-     endif %}
-{%-   endif %}
-   */
-  {{method.name}}(
-{%-   for parameter in method.parameters -%}
-{{parameter.name|sanitize_identifier}}{% if not loop.last %}, {% endif %}
-{%-   endfor -%}
-) {}
-{%- endfor %}
-{%- endmacro %}
-
-/** @interface */
-{{module.namespace}}.{{interface.name}}Interface = class {
-{{ generateInterfaceClassBody() }}
-};
-
-{{module.namespace}}.{{interface.name}}Request = class {
-  /** @param {!MojoHandle} handle */
-  constructor(handle) {}
-};
-
-/** @implements { {{module.namespace}}.{{interface.name}}Interface } */
-{{module.namespace}}.{{interface.name}}Proxy = class {
-  constructor() {
-    /** @public {!{
-     *    createRequest: function(): !{{module.namespace}}.{{interface.name}}Request,
-     *    close: function(),
-     *    flushForTesting: function(): !Promise
-     *  }}
-     */
-    this.$;
-
-    /** @public {!mojo.internal.ConnectionErrorEventRouter} */
-    this.onConnectionError;
-  }
-{{ generateInterfaceClassBody() }}
-};
-
-{{module.namespace}}.{{interface.name}} = class {
-  /** @param {!{{module.namespace}}.{{interface.name}}Interface} impl */
-  constructor(impl) {}
-
-  /**
-   * @param {!MojoHandle} handle
-   */
-  bindHandle(handle) {}
-
-  /**
-   * @return {!{{module.namespace}}.{{interface.name}}Proxy }
-   */
-  static getProxy() {}
-
-  /**
-   * @return {!{{module.namespace}}.{{interface.name}}Proxy }
-   */
-  createProxy() {}
-};
-
-/** @const {!string} */
-{{module.namespace}}.{{interface.name}}.$interfaceName;
-
-{{module.namespace}}.{{interface.name}}CallbackRouter = class {
-  constructor() {
-{%- for method in interface.methods %}
-    /** @public {!mojo.internal.InterfaceCallbackTarget} */
-    this.{{method.name}};
-{%- endfor %}
-  }
-
-  /**
-   * @param {!MojoHandle} handle
-   */
-  bindHandle(handle) {}
-
-  /**
-   * @return {!{{module.namespace}}.{{interface.name}}Proxy }
-   */
-  createProxy() {}
-
-  /**
-   * @param {number} id An ID returned by a prior call to addListener.
-   * @return {boolean} True iff the identified listener was found and removed.
-   */
-  removeListener(id) {}
-};
-
-{#--- Enum definitions #}
-{% for enum in interface.enums %}
-/** @enum {number} */
-{{module.namespace}}.{{interface.name}}.{{enum.name}} = {};
-{%-   for field in enum.fields %}
-{{module.namespace}}.{{interface.name}}.{{enum.name}}.{{field.name}};
-{%-   endfor %}
-{%- endfor %}

mojo/public/tools/bindings/generators/js_templates/lite/module.externs.tmpl

-// Copyright 2018 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.
-
-{# Note that goog.provide is understood by the Closure Compiler even if the
-   Closure base library is unavailable. See https://crbug.com/898692 #}
-{#--- Constant definitions #}
-{%- for constant in module.constants %}
-/** @type { {{constant.kind|closure_type_with_nullability }} } */
-goog.provide('{{module.namespace}}.{{constant.name}}');
-{%- endfor %}
-
-{#--- Enum definitions #}
-{% for enum in enums %}
-/** @enum {number} */
-{{module.namespace}}.{{enum.name}} = {};
-{%-   for field in enum.fields %}
-{{module.namespace}}.{{enum.name}}.{{field.name}};
-{%-   endfor %}
-{%- endfor %}
-
-{#--- Interface definitions #}
-{%- for interface in interfaces -%}
-{%-   include "lite/interface_externs.tmpl" %}
-{%  endfor -%}
-
-{#--- Struct definitions #}
-{%- for struct in structs -%}
-{%-   include "lite/struct_externs.tmpl" %}
-{%  endfor -%}
-
-{#--- Union definitions #}
-{%- for union in unions -%}
-{%-   include "lite/union_externs.tmpl" %}
-{%  endfor -%}

mojo/public/tools/bindings/generators/js_templates/lite/module_definition.tmpl

 {#--- Constants #}
 {%- for constant in module.constants %}
+{%  if generate_closure_exports -%}
+goog.provide('{{module.namespace}}.{{constant.name}}');
+
+{%- endif %}
 /**
  * @const { {{constant.kind|lite_closure_type_with_nullability}} }
  * @export
@@ -9,9 +13,9 @@
 {%- endfor %}
 
 {#--- Enums #}
-{% from "lite/enum_definition.tmpl" import enum_def %}
+{% from "lite/enum_definition.tmpl" import enum_def with context %}
 {%- for enum in enums %}
-{{enum_def("%s.%s"|format(module.namespace, enum.name), enum)}}
+{{enum_def(module.namespace, module.namespace, enum)}}
 {%  endfor %}
 
 {#--- Interface definitions #}
@@ -24,19 +28,25 @@
  # mojo.internal.Struct and mojo.internal.Union will fix-up the object
  # appropriately, and we don't want Closure to complain. #}
 {%  for struct in structs %}
+{%  if generate_closure_exports -%}
+goog.provide('{{module.namespace}}.{{struct.name}}Spec');
+{%- endif %}
 /**
- * @const {!Object}
+ * @const { {$:!mojo.internal.MojomType}}
  * @export
  */
-{{module.namespace}}.{{struct.name}} =
+{{module.namespace}}.{{struct.name}}Spec =
     { $: /** @type {!mojo.internal.MojomType} */ ({}) };
 {% endfor %}
 {%- for union in unions %}
+{%  if generate_closure_exports -%}
+goog.provide('{{module.namespace}}.{{union.name}}Spec');
+{%- endif %}
 /**
- * @const {!Object}
+ * @const { {$:!mojo.internal.MojomType} }
  * @export
  */
-{{module.namespace}}.{{union.name}} =
+{{module.namespace}}.{{union.name}}Spec =
     { $: /** @type {!mojo.internal.MojomType} */ ({}) };
 {% endfor %}
 

mojo/public/tools/bindings/generators/js_templates/lite/mojom-lite.js.tmpl

@@ -8,11 +8,6 @@ goog.require('mojo.internal');
 {%- if interfaces %}
 goog.require('mojo.internal.interfaceSupport');
 {%- endif %}
-
-{% for import in imports -%}
-goog.require('{{import.namespace}}');
-{% endfor %}
-goog.provide('{{module.namespace}}');
 {% endif %}
 
 mojo.internal.exportModule('{{module.namespace}}');

mojo/public/tools/bindings/generators/js_templates/lite/struct_definition.tmpl

@@ -7,13 +7,14 @@
     {{constant.value|expression_to_text_lite}};
 {%  endfor %}
 
-{%- from "lite/enum_definition.tmpl" import enum_def %}
+{%- from "lite/enum_definition.tmpl" import enum_def with context %}
 {%  for enum in struct.enums %}
-{{enum_def("%s.%s.%s"|format(module.namespace, struct.name, enum.name), enum)}}
+{{enum_def("%s.%sSpec"|format(module.namespace, struct.name),
+           "%s.%s"|format(module.namespace, struct.name), enum)}}
 {%  endfor %}
 
 mojo.internal.Struct(
-    {{module.namespace}}.{{struct.name}}.$,
+    {{module.namespace}}.{{struct.name}}Spec.$,
     '{{struct.name}}',
     {{struct.packed|payload_size}},
     [
@@ -31,3 +32,21 @@ mojo.internal.Struct(
 {%-   endif %}
 {%- endfor %}
     ]);
+
+{%  if generate_closure_exports -%}
+goog.provide('{{module.namespace}}.{{struct.name}}');
+
+{% if struct.packed.packed_fields %}
+/**
+ * @typedef { {
+{%- for packed_field in struct.packed.packed_fields %}
+ *   {{packed_field.field.name}}: {{packed_field.field.kind|lite_closure_field_type}},
+{%-  endfor %}
+ * } }
+ */
+{% else %}
+/** @typedef {Object} */
+{% endif %}
+{{module.namespace}}.{{struct.name}};
+
+{%- endif %}

mojo/public/tools/bindings/generators/js_templates/lite/struct_externs.tmpl

-{# Note that goog.provide is understood by the Closure Compiler even if the
-   Closure base library is unavailable. See https://crbug.com/898692 #}
-goog.provide('{{module.namespace}}.{{struct.name}}');
-
-{% if struct.packed.packed_fields %}
-/**
- * @typedef { {
-{%- for packed_field in struct.packed.packed_fields %}
- *   {{packed_field.field.name}}: {{packed_field.field.kind|lite_closure_field_type}},
-{%-  endfor %}
- * } }
- */
-{% else %}
-/** @typedef {Object} */
-{% endif %}
-{{module.namespace}}.{{struct.name}};
-
-{#--- Enum definitions #}
-{% for enum in struct.enums %}
-/** @enum {number} */
-{{module.namespace}}.{{struct.name}}.{{enum.name}} = {};
-{%-   for field in enum.fields %}
-{{module.namespace}}.{{struct.name}}.{{enum.name}}.{{field.name}};
-{%-   endfor %}
-{%- endfor %}

mojo/public/tools/bindings/generators/js_templates/lite/test/BUILD.gn

@@ -20,6 +20,6 @@ js_type_check("closure_compile") {
 
 js_library("test") {
   deps = [
-    ":mojo_bindings_js_externs",
+    ":mojo_bindings_js_library_for_compile",
   ]
 }

mojo/public/tools/bindings/generators/js_templates/lite/test/test.js

@@ -7,10 +7,13 @@ async function testFunction() {
   let proxy = test.mojom.TestPageHandler.getProxy()
 
   // Type infers {?{values: !Array<!string>}} from Promise return type.
-  let result = await proxy.method1();
+  let result = await proxy.method1(' ', 5);
 
   /** @type {Array<string>} */
   let values = result.values;
+
+  /** @type {test.mojom.TestStruct} */
+  let testStruct = result.ts
 }
 
 /** @implements {test.mojom.TestPageInterface} */

mojo/public/tools/bindings/generators/js_templates/lite/test/test.test-mojom

@@ -24,7 +24,7 @@ struct TestStruct {
 };
 
 interface TestPageHandler {
-  Method1() => (array<string> values);
+  Method1(string p1, int32 p2) => (array<string> values, TestStruct ts);
 };
 
 interface TestPage {

mojo/public/tools/bindings/generators/js_templates/lite/union_definition.tmpl

 
 mojo.internal.Union(
-    {{module.namespace}}.{{union.name}}.$, '{{union.name}}',
+    {{module.namespace}}.{{union.name}}Spec.$, '{{union.name}}',
     {
 {%- for field in union.fields %}
       '{{field.name}}': {
@@ -12,3 +12,12 @@ mojo.internal.Union(
       },
 {%- endfor %}
     });
+
+/**
+ * @typedef { {
+{%- for field in union.fields %}
+ *   {{field.name}}: ({{field.kind|lite_closure_type_with_nullability}}|undefined),
+{%-  endfor %}
+ * } }
+ */
+{{module.namespace}}.{{union.name}};

mojo/public/tools/bindings/generators/js_templates/lite/union_externs.tmpl

-{# Note that goog.provide is understood by the Closure Compiler even if the
-   Closure base library is unavailable. See https://crbug.com/898692 #}
-goog.provide('{{module.namespace}}.{{union.name}}');
-
-{{module.namespace}}.{{union.name}} = class {
-  constructor() {
-{%- for field in fields %}
-    /** @type { {{field.kind|lite_closure_type_with_nullability}} } */
-    this.{{field.name}};
-{%-  endfor %}
-  }
-};

mojo/public/tools/bindings/generators/mojom_js_generator.py

@@ -341,10 +341,6 @@ class Generator(generator.Generator):
   def _GenerateLiteBindingsForCompile(self):
     return self._GetParameters(for_compile=True)
 
-  @UseJinja("lite/module.externs.tmpl")
-  def _GenerateLiteExterns(self):
-    return self._GetParameters()
-
   def GenerateFiles(self, args):
     if self.variant:
       raise Exception("Variants not supported in JavaScript bindings.")
@@ -362,8 +358,6 @@ class Generator(generator.Generator):
       self.Write(self._GenerateLiteBindings(), "%s-lite.js" % self.module.path)
       self.Write(self._GenerateLiteBindingsForCompile(),
           "%s-lite-for-compile.js" % self.module.path)
-      self.Write(self._GenerateLiteExterns(),
-                 "%s-lite.externs.js" % self.module.path)
 
   def _SetUniqueNameForImports(self):
     used_names = set()
@@ -532,19 +526,20 @@ class Generator(generator.Generator):
     if named_kind.module:
       name.append(named_kind.module.namespace)
     if named_kind.parent_kind:
-      name.append(named_kind.parent_kind.name)
+      name.append(named_kind.parent_kind.name + "Spec")
     name.append(named_kind.name)
     name = ".".join(name)
 
     if (mojom.IsStructKind(kind) or mojom.IsUnionKind(kind) or
         mojom.IsEnumKind(kind)):
-      return "%s.$" % name
+      return "%sSpec.$" % name
     if mojom.IsInterfaceKind(kind):
       return "mojo.internal.InterfaceProxy(%sProxy)" % name
     if mojom.IsInterfaceRequestKind(kind):
       return "mojo.internal.InterfaceRequest(%sRequest)" % name
     if mojom.IsAssociatedInterfaceKind(kind):
-      return "mojo.internal.AssociatedInterfaceProxy(%sAssociatedProxy)" % (
+      # TODO(rockot): Implement associated interfaces.
+      return "mojo.internal.AssociatedInterfaceProxy(%sProxy)" % (
           name)
     if mojom.IsAssociatedInterfaceRequestKind(kind):
       return "mojo.internal.AssociatedInterfaceRequest(%s)" % name
@@ -584,7 +579,7 @@ class Generator(generator.Generator):
       if mojom.IsStructKind(field.kind):
         assert field.default == "default"
         return "null";
-      return self._ExpressionToText(field.default)
+      return self._ExpressionToTextLite(field.default)
     if field.kind in mojom.PRIMITIVES:
       return _kind_to_javascript_default_value[field.kind]
     if mojom.IsEnumKind(field.kind):

mojo/public/tools/bindings/mojom.gni

@@ -1219,7 +1219,6 @@ template("mojom") {
             "$target_gen_dir/$source.externs.js",
             "$target_gen_dir/$source-lite.js",
             "$target_gen_dir/$source-lite-for-compile.js",
-            "$target_gen_dir/$source-lite.externs.js",
           ]
         }
 
@@ -1293,48 +1292,30 @@ template("mojom") {
       }
     }
 
-    if (enable_mojom_closure_compile) {
-      js_library_for_compile_target_name =
-          "${target_name}_js_library_for_compile"
-      if (defined(invoker.sources)) {
-        generator_js_lite_for_compile_outputs =
-            [ "{{source_gen_dir}}/{{source_file_part}}-lite-for-compile.js" ]
-        js_library(js_library_for_compile_target_name) {
-          extra_public_deps = [ ":$generator_js_target_name" ]
-          sources = process_file_template(invoker.sources,
-                                          generator_js_lite_for_compile_outputs)
-
-          deps = []
-          foreach(d, all_deps) {
-            full_name = get_label_info(d, "label_no_toolchain")
-            deps += [ "${full_name}_js_library_for_compile" ]
-          }
-        }
-      } else {
-        group(js_library_for_compile_target_name) {
-        }
-      }
-    }
-
-    js_externs_target_suffix = "_js_externs"
-    js_externs_target_name = "${target_name}${js_externs_target_suffix}"
+    js_library_for_compile_target_name = "${target_name}_js_library_for_compile"
     if (defined(invoker.sources)) {
-      js_library(js_externs_target_name) {
-        sources = []
+      generator_js_lite_for_compile_outputs =
+          [ "{{source_gen_dir}}/{{source_file_part}}-lite-for-compile.js" ]
+      js_library(js_library_for_compile_target_name) {
         extra_public_deps = [ ":$generator_js_target_name" ]
-        externs_list = [ "${externs_path}/mojo.js" ]
-        externs_list += process_file_template(
-                invoker.sources,
-                [ "{{source_gen_dir}}/{{source_file_part}}-lite.externs.js" ])
+        sources = process_file_template(invoker.sources,
+                                        generator_js_lite_for_compile_outputs)
 
+        externs_list = [
+          "${externs_path}/mojo_core.js",
+          "${externs_path}/pending.js",
+        ]
         deps = []
+        if (!defined(invoker.disallow_native_types)) {
+          deps += [ "//mojo/public/js:bindings_lite_sources" ]
+        }
         foreach(d, all_deps) {
           full_name = get_label_info(d, "label_no_toolchain")
-          deps += [ "${full_name}${js_externs_target_suffix}" ]
+          deps += [ "${full_name}_js_library_for_compile" ]
         }
       }
     } else {
-      group(js_externs_target_name) {
+      group(js_library_for_compile_target_name) {
       }
     }
   }

ui/webui/resources/cr_components/chromeos/multidevice_setup/BUILD.gn

@@ -26,14 +26,14 @@ js_library("button_bar") {
 
 js_library("fake_mojo_service") {
   deps = [
-    "//chromeos/services/multidevice_setup/public/mojom:mojom_js_externs",
+    "//chromeos/services/multidevice_setup/public/mojom:mojom_js_library_for_compile",
     "//ui/webui/resources/js:cr",
   ]
 }
 
 js_library("mojo_api") {
   deps = [
-    "//chromeos/services/multidevice_setup/public/mojom:mojom_js_externs",
+    "//chromeos/services/multidevice_setup/public/mojom:mojom_js_library_for_compile",
     "//ui/webui/resources/js:cr",
   ]
 }