Migrate Chromium PDF viewer to use Media App ink resources.

This lets the Chromium PDF viewer get it's ink resources from
chormeos/componeonts/media_app_ui/resources/prod/lib/ink which is
built internally and shipped into CrOS as part of the media app.
The resources themselves are bundled via grit in
chromeos_media_app_bundle_resources.h.

In doing so we add the BUILD flag enable_use_media_app_ink:
* if true, don't build third_party/ink and thus don't create
gen/third_party/ink/ink_resources.pak, instead get resources from
gen/chromeos/chromeos_media_app_bundle_resources.pak
* if false, do what TOT currently does and build third_party/ink

This allows us to only ever build 1 set of ink resources into the
Chrome OS binary and avoid bloating the OS by ~ +2.4MB.
See size increase in
http://b/170161460#comment18 for more context.

This change also updates the externs of the ink library which works
with new ink resources and also the older ink resources
(third_party/ink/build) checked into TOT.

Regression tested with various builds of TOT, new ink resources & TOT
and new ink resources & this cl for the resource plumbing
(grd, flags etc) see regression testing in
http://b/170161460#comment18 for more context.

Note:
* currently enable_use_media_app_ink is just =
enable_cros_media_app but that might change.
* linux-chromeos-chrome trybot will fail until http://cl/347557653
lands and rolls into chromium. There is some time between
http://cl/347557653 rolling in and this cl landing which may mean the
OS is bloated with 2 copies of ink resources but this should be ok as
long as this is done before branch and in reality they will land in
O(day) time.

Bug: b/170161460, 1150244
Change-Id: I8e01ce9863dd00bcbab7b322ad3cf33c1424ec6f
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2542926Reviewed-by: David Lei <dlei@google.com>
Reviewed-by: Scott Violet <sky@chromium.org>
Reviewed-by: Bugs Nash <bugsnash@chromium.org>
Commit-Queue: David Lei <dlei@google.com>
Cr-Commit-Position: refs/heads/master@{#837450}

chrome/BUILD.gn

@@ -1372,7 +1372,8 @@ group("extra_resources") {
     "//components/autofill/core/browser:autofill_address_rewriter_resources",
   ]
 
-  if (is_chromeos_ash) {
+  if (is_chromeos_ash && !enable_use_media_app_ink) {
+    # TODO(crbug/1150244): Remove when enable_use_media_app_ink is default true.
     public_deps += [ "//third_party/ink:ink_resources" ]
   }
 }

chrome/browser/extensions/BUILD.gn

@@ -5,6 +5,7 @@
 import("//build/config/chromeos/ui_mode.gni")
 import("//build/config/features.gni")
 import("//build/config/ui.gni")
+import("//chrome/browser/resources/pdf/ink/ink.gni")
 import("//chrome/common/features.gni")
 import("//chromeos/components/chromebox_for_meetings/buildflags/buildflags.gni")
 import("//components/nacl/features.gni")
@@ -926,6 +927,10 @@ static_library("extensions") {
     "//url",
   ]
 
+  if (is_chromeos_ash) {
+    deps += [ "//chromeos/resources:media_app_bundle_resources_grit" ]
+  }
+
   if (enable_autofill_assistant_api) {
     sources += [
       "api/autofill_assistant_private/autofill_assistant_private_api.cc",
@@ -1029,6 +1034,7 @@ static_library("extensions") {
       "//chrome/browser/chromeos/crostini:crostini_installer_types_mojom",
       "//chrome/browser/devtools",
       "//chrome/browser/nearby_sharing/common",
+      "//chrome/browser/resources/pdf/ink:buildflags",
       "//chrome/browser/ui/webui/settings/chromeos/constants:mojom",
       "//chromeos",
       "//chromeos/attestation",

chrome/browser/extensions/chrome_component_extension_resource_manager.cc

@@ -28,15 +28,23 @@
 #include "base/command_line.h"
 #include "chrome/browser/browser_process.h"
 #include "chrome/browser/chromeos/file_manager/file_manager_string_util.h"
-#include "third_party/ink/grit/ink_resources.h"
+#include "chrome/browser/resources/pdf/ink/buildflags.h"
 #include "ui/file_manager/grit/file_manager_gen_resources_map.h"
 #include "ui/file_manager/grit/file_manager_resources_map.h"
-#endif
+
+#if BUILDFLAG(ENABLE_USE_MEDIA_APP_INK)
+#include "chromeos/grit/chromeos_media_app_bundle_resources.h"
+#else
+// TODO(crbug/1150244): Remove when deprecated.
+#include "third_party/ink/grit/ink_resources.h"
+#endif  // BUILDFLAG(ENABLE_USE_MEDIA_APP_INK)
+
+#endif  // BUILDFLAG(IS_CHROMEOS_ASH)
 
 #if BUILDFLAG(ENABLE_PDF)
 #include <utility>
 #include "chrome/browser/pdf/pdf_extension_util.h"
-#endif
+#endif  // BUILDFLAG(ENABLE_PDF)
 
 namespace extensions {
 
@@ -82,11 +90,21 @@ ChromeComponentExtensionResourceManager::Data::Data() {
 #if BUILDFLAG(IS_CHROMEOS_ASH)
     {"chrome_app/chrome_app_icon_32.png", IDR_CHROME_APP_ICON_32},
     {"chrome_app/chrome_app_icon_192.png", IDR_CHROME_APP_ICON_192},
+#if BUILDFLAG(ENABLE_USE_MEDIA_APP_INK)
+    // Built in go/bbsrc/lib/BUILD
+    {"pdf/ink/ink_engine_ink.worker.js",
+     IDR_MEDIA_APP_INK_ENGINE_INK_WORKER_JS},
+    {"pdf/ink/ink_engine_ink.wasm", IDR_MEDIA_APP_INK_ENGINE_INK_WASM},
+    {"pdf/ink/ink_lib_binary.js", IDR_MEDIA_APP_EXPORT_CANVAS_BIN_JS},
+    {"pdf/ink/ink_loader.js", IDR_MEDIA_APP_INK_JS},
+#else
+    // TODO(crbug/1150244): Remove these when deprecated.
     {"pdf/ink/ink_lib_binary.js", IDR_INK_LIB_BINARY_JS},
     {"pdf/ink/wasm_ink.worker.js", IDR_INK_WORKER_JS},
     {"pdf/ink/wasm_ink.wasm", IDR_INK_WASM},
     {"pdf/ink/ink_loader.js", IDR_INK_LOADER_JS},
-#endif
+#endif  // BUILDFLAG(ENABLE_USE_MEDIA_APP_INK)
+#endif  // BUILDFLAG(IS_CHROMEOS_ASH)
   };
 
   AddComponentResourceEntries(kComponentExtensionResources,
@@ -140,8 +158,8 @@ void ChromeComponentExtensionResourceManager::Data::AddComponentResourceEntries(
   gen_folder_path = gen_folder_path.NormalizePathSeparators();
 
   for (size_t i = 0; i < size; ++i) {
-    base::FilePath resource_path = base::FilePath().AppendASCII(
-        entries[i].name);
+    base::FilePath resource_path =
+        base::FilePath().AppendASCII(entries[i].name);
     resource_path = resource_path.NormalizePathSeparators();
 
     if (!gen_folder_path.IsParent(resource_path)) {

chrome/browser/resources/pdf/elements/viewer-ink-host.js

@@ -224,7 +224,7 @@ Polymer({
     this.ink_.addUndoStateListener(
         e => this.dispatchEvent(
             new CustomEvent('undo-state-changed', {detail: e})));
-    this.ink_.setPDF(data);
+    await this.ink_.setPDF(data);
     this.state_ = State.ACTIVE;
     this.viewportChanged();
     // Wait for the next task to avoid a race where Ink drops the background

chrome/browser/resources/pdf/ink/BUILD.gn

@@ -2,6 +2,8 @@
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
+import("//build/buildflag_header.gni")
+import("//chrome/browser/resources/pdf/ink/ink.gni")
 import("//third_party/closure_compiler/compile_js.gni")
 
 js_type_check("closure_compile") {
@@ -10,8 +12,17 @@ js_type_check("closure_compile") {
 
 js_library("ink_api") {
   deps = [ "..:annotation_tool" ]
-  externs_list = [
-    "//third_party/ink/build/ink_lib_externs.js",
-    "$externs_path/pending.js",
-  ]
+  externs_list = [ "$externs_path/pending.js" ]
+
+  if (enable_use_media_app_ink) {
+    externs_list += [ "drawing_canvas_externs.js" ]
+  } else {
+    externs_list += [ "//third_party/ink/build/ink_lib_externs.js" ]
+  }
+}
+
+buildflag_header("buildflags") {
+  header = "buildflags.h"
+
+  flags = [ "ENABLE_USE_MEDIA_APP_INK=$enable_use_media_app_ink" ]
 }

chrome/browser/resources/pdf/ink/drawing_canvas_externs.js

+// Copyright 2020 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.
+
+/**
+ * @fileoverview @externs for export-safe ink.Canvas wrapper.
+ *
+ * This file defines types and an interface, drawings.Canvas, that are safe for
+ * export and satisfy the usage in the Chrome PDF annotation mode.
+ */
+
+/** @const Namespace */
+const drawings = {};
+
+/**
+ * A simple rectangle type.  The coordinate system depends on context.
+ *
+ * @typedef {{left: number, top: number, right: number, bottom: number}}
+ */
+drawings.Box;
+
+/**
+ * A PointerEvent-like record type that can be used to pass PointerEvents or an
+ * equivalent object with adjusted fields to the Ink engine.
+ *
+ * Ink depends on the timestamps of events and offsetX/Y, none of which can be
+ * set in the synthetic PointerEvent constructor.
+ *
+ * @typedef {{
+ *   type: string,
+ *   timeStamp: number,
+ *   pointerType: string,
+ *   pointerId: number,
+ *   offsetX: number,
+ *   offsetY: number,
+ *   pressure: number,
+ *   button: number,
+ *   buttons: number,
+ * }}
+ */
+drawings.InputEvent;
+
+/**
+ * Tool types supported in the Ink engine.
+ *
+ * See http://go/ink-tools for details on each tool.
+ *
+ * Note: These values map to the AnnotationTool definition in Chromium.
+ *
+ * @enum {string}
+ */
+drawings.ToolType = {
+  MARKER: 'marker',
+  PEN: 'pen',
+  HIGHLIGHTER: 'highlighter',
+  ERASER: 'eraser',
+};
+
+/** @typedef {{canUndo: boolean, canRedo: boolean}} */
+drawings.UndoState;
+
+/**
+ * The main interface to Ink.
+ *
+ * Many of these functions ultimately delegate to C++ compiled to WebAssembly.
+ * The WebAssembly module depends on global state, thus it is only safe to have
+ * one instance at a time.
+ *
+ * Use the static execute function to get an instance of the class.
+ *
+ * @interface
+ */
+drawings.Canvas = class {
+  /**
+   * Factory function for the Canvas instance.
+   *
+   * @param {!Element} parent Element to render the canvas into.
+   * @return {!Promise<!drawings.Canvas>}
+   */
+  static async execute(parent) {}
+
+  /**
+   * Notifies the attached listener when the undo/redo state changes.
+   *
+   * @param {function(!drawings.UndoState):undefined} listener
+   */
+  addUndoRedoListener(listener) {}
+
+  /**
+   * Sets the PDF to edit in the Ink engine.  This resets any existing
+   * annotations, the camera, and any other state in the engine.
+   *
+   * @param {!ArrayBuffer|!Uint8Array} buffer
+   * @return {!Promise<undefined>}
+   */
+  async setPDF(buffer) {}
+
+  /**
+   * Returns a copy of the currently-edited PDF with the Ink annotations
+   * serialized into it.
+   *
+   * @return {!Uint8Array}
+   */
+  getPDF() {}
+
+  /**
+   * Returns the currently-edited PDF with the Ink annotations serialized into
+   * it.  This destructively moves the PDF out of the Ink engine, and the engine
+   * should not be issued any further strokes or functions calls until setPDF is
+   * called again.
+   *
+   * @return {!Uint8Array}
+   */
+  getPDFDestructive() {}
+
+  /**
+   * Set the camera to the provided box in PDF coordinates.
+   *
+   * @param {!drawings.Box} camera
+   */
+  setCamera(camera) {}
+
+  /**
+   * Set the tool parameters in the Ink engine.
+   *
+   * See AnnotationTool in Chromium.
+   *
+   * @param {{
+   *   tool: (!drawings.ToolType|string),
+   *   color: (string|undefined),
+   *   size: (number|undefined),
+   * }} toolParams
+   */
+  setTool({tool, color, size}) {}
+
+  /**
+   * Returns a Promise that is resolved when all previous asynchronous engine
+   * operations are completed.  Use this prior to calling getPDF to ensure all
+   * Ink strokes are serialized.
+   *
+   * @return {!Promise<undefined>}
+   */
+  flush() {}
+
+  /**
+   * Set the out of bounds color drawn around the PDF and between pages.
+   *
+   * @param {string} color
+   */
+  setOutOfBoundsColor(color) {}
+
+  /**
+   * Set the image used as the page border around each page.  Must be a data or
+   * Object URL to a nine-patch PNG image.
+   *
+   * @param {string} url
+   */
+  setBorderImage(url) {}
+
+  /**
+   * Set the page layout to vertical (default) and the given spacing.
+   *
+   * @param {number} spacing
+   */
+  setVerticalPageLayout(spacing) {}
+
+  /**
+   * Dispatch the given PointerEvent-like to the Ink engine.
+   *
+   * This will cause the engine to draw a line, erase, etc. depending on the
+   * current tool parameters.  Note that the Ink engine depends on the timestamp
+   * when processing events, but synthetic PointerEvents have the timestamp set
+   * to the creation time and can't be changed.  Instead dispatch an object
+   * literal with the same fields with the desired timestamp.
+   *
+   * @param {!drawings.InputEvent} event
+   */
+  dispatchInput(event) {}
+
+  /** Undo the most recent operation. */
+  undo() {}
+
+  /** Redo the last undone operation. */
+  redo() {}
+};

chrome/browser/resources/pdf/ink/ink.gni

+import("//build/config/chrome_build.gni")
+import("//chromeos/components/media_app_ui/media_app_ui.gni")
+
+declare_args() {
+  enable_use_media_app_ink = enable_cros_media_app
+}

chrome/browser/resources/pdf/ink/ink_api.js

@@ -21,11 +21,11 @@ class InkAPI {
   /**
    * @param {!ArrayBuffer} buffer
    */
-  setPDF(buffer) {
+  async setPDF(buffer) {
     // We change the type from ArrayBuffer to Uint8Array due to the consequences
     // of the buffer being passed across the iframe boundary. This realm has a
     // different ArrayBuffer constructor than `buffer`.
-    this.canvas_.setPDF(new Uint8Array(buffer));
+    return this.canvas_.setPDF(new Uint8Array(buffer));
   }
 
   /**

chrome/chrome_paks.gni

@@ -5,6 +5,7 @@
 import("//build/config/chromeos/ui_mode.gni")
 import("//build/config/locales.gni")
 import("//chrome/browser/buildflags.gni")
+import("//chrome/browser/resources/pdf/ink/ink.gni")
 import("//chrome/common/features.gni")
 import("//extensions/buildflags/buildflags.gni")
 import("//ui/base/ui_features.gni")
@@ -192,7 +193,6 @@ template("chrome_extra_paks") {
         "$root_gen_dir/chromeos/chromeos_resources.pak",
         "$root_gen_dir/chromeos/chromeos_scanning_app_resources.pak",
         "$root_gen_dir/chromeos/connectivity_diagnostics_resources.pak",
-        "$root_gen_dir/third_party/ink/ink_resources.pak",
         "$root_gen_dir/ui/file_manager/file_manager_gen_resources.pak",
         "$root_gen_dir/ui/file_manager/file_manager_resources.pak",
       ]
@@ -217,11 +217,17 @@ template("chrome_extra_paks") {
         "//chromeos/resources:media_app_resources",
         "//chromeos/resources:print_management_resources",
         "//chromeos/resources:scanning_app_resources",
-        "//third_party/ink:ink_resources",
         "//ui/file_manager:file_manager_gen_resources",
         "//ui/file_manager:resources",
       ]
 
+      if (!enable_use_media_app_ink) {
+        # TODO(crbug/1150244): Remove when enable_use_media_app_ink is default
+        # true.
+        sources += [ "$root_gen_dir/third_party/ink/ink_resources.pak" ]
+        deps += [ "//third_party/ink:ink_resources" ]
+      }
+
       if (!is_official_build) {
         sources += [
           "$root_gen_dir/chromeos/chromeos_file_manager_resources.pak",