Refactor get_salient_image_url.js to use DocumentImageExtractor

Refactor get_salient_image_url.js to use the DocumentImageExtractor.
Move get_salient_image_url.js into components so it accessible for
iOS as well.

BUG=454623

Review URL: https://codereview.chromium.org/1036113002

Cr-Commit-Position: refs/heads/master@{#331807}

15 files changed, 296 insertions, 102 deletions

diff --git a/chrome/browser/browser_resources.grd b/chrome/browser/browser_resources.grd
index b30eae2..3987476 100644
--- a/chrome/browser/browser_resources.grd
+++ b/chrome/browser/browser_resources.grd
@@ -146,9 +146,6 @@
       <include name="IDR_FEEDBACK_MANIFEST" file="resources\feedback\manifest.json" type="BINDATA" />
       <include name="IDR_FLAGS_HTML" file="resources\flags.html" flattenhtml="true" type="BINDATA" />
       <include name="IDR_FLAGS_JS" file="resources\flags.js" type="BINDATA" />
-      <if expr="is_android">
-        <include name="IDR_GET_SALIENT_IMAGE_URL_JS" file="resources\get_salient_image_url.js" type="BINDATA" />
-      </if>
       <if expr="_google_chrome or enable_hangout_services_extension">
         <!-- Hangout Services extension, included in Google Chrome builds only. -->
         <include name="IDR_HANGOUT_SERVICES_MANIFEST" file="resources\hangout_services\manifest.json" type="BINDATA" />
diff --git a/chrome/browser/enhanced_bookmarks/android/DEPS b/chrome/browser/enhanced_bookmarks/android/DEPS
index 5d93983..c3e3c3d 100644
--- a/chrome/browser/enhanced_bookmarks/android/DEPS
+++ b/chrome/browser/enhanced_bookmarks/android/DEPS
@@ -1,3 +1,4 @@
 include_rules = [
   "+chrome/renderer/chrome_isolated_world_ids.h",
+  "+grit/enhanced_bookmarks_resources.h",
 ]
diff --git a/chrome/browser/enhanced_bookmarks/android/bookmark_image_service_android.cc b/chrome/browser/enhanced_bookmarks/android/bookmark_image_service_android.cc
index 61e5b3b..5f8bd9c 100644
--- a/chrome/browser/enhanced_bookmarks/android/bookmark_image_service_android.cc
+++ b/chrome/browser/enhanced_bookmarks/android/bookmark_image_service_android.cc
@@ -17,7 +17,7 @@
 #include "content/public/browser/navigation_entry.h"
 #include "content/public/browser/render_frame_host.h"
 #include "content/public/browser/web_contents.h"
-#include "content/public/common/referrer.h"
+#include "grit/enhanced_bookmarks_resources.h"
 #include "net/base/load_flags.h"
 #include "skia/ext/image_operations.h"
 #include "ui/base/device_form_factor.h"
@@ -87,7 +87,7 @@ void BookmarkImageServiceAndroid::RetrieveSalientImage(
 }
 
 void BookmarkImageServiceAndroid::RetrieveSalientImageFromContext(
-    content::RenderFrameHost* render_frame_host,
+    content::WebContents* web_contents,
     const GURL& page_url,
     bool update_bookmark) {
   DCHECK_CURRENTLY_ON(content::BrowserThread::UI);
@@ -109,18 +109,25 @@ void BookmarkImageServiceAndroid::RetrieveSalientImageFromContext(
     return;
   }
 
-  if (script_.empty()) {
-    script_ =
-        base::UTF8ToUTF16(ResourceBundle::GetSharedInstance()
-                              .GetRawDataResource(IDR_GET_SALIENT_IMAGE_URL_JS)
-                              .as_string());
+  if (dom_initializer_script_.empty()) {
+    dom_initializer_script_ =
+        base::UTF8ToUTF16(
+            ResourceBundle::GetSharedInstance()
+                .GetRawDataResource(IDR_DOM_INITIALIZER_GEN_JS)
+                .as_string());
   }
 
+  blink::WebReferrerPolicy policy =
+      web_contents->GetController().GetVisibleEntry()->GetReferrer().policy;
+
+  content::RenderFrameHost* render_frame_host = web_contents->GetMainFrame();
+
   render_frame_host->ExecuteJavaScriptInIsolatedWorld(
-      script_,
+      dom_initializer_script_,
       base::Bind(
-          &BookmarkImageServiceAndroid::RetrieveSalientImageFromContextCallback,
-          base::Unretained(this), page_url, update_bookmark),
+          &BookmarkImageServiceAndroid::InitializeDomCallback,
+          base::Unretained(this), policy, render_frame_host, page_url,
+          update_bookmark),
       chrome::ISOLATED_WORLD_ID_CHROME_INTERNAL);
 }
 
@@ -141,13 +148,36 @@ void BookmarkImageServiceAndroid::FinishSuccessfulPageLoadForTab(
     urls.push_back(entry_original_url);
   for (GURL url : urls) {
     if (enhanced_bookmark_model_->bookmark_model()->IsBookmarked(url)) {
-      RetrieveSalientImageFromContext(web_contents->GetMainFrame(), url,
+      RetrieveSalientImageFromContext(web_contents, url,
                                       update_bookmark);
     }
   }
 }
 
+void BookmarkImageServiceAndroid::InitializeDomCallback(
+    blink::WebReferrerPolicy policy,
+    content::RenderFrameHost* render_frame_host,
+    const GURL& page_url,
+    bool update_bookmark,
+    const base::Value* result) {
+  if (get_salient_image_url_script_.empty()) {
+    get_salient_image_url_script_ =
+        base::UTF8ToUTF16(
+            ResourceBundle::GetSharedInstance()
+                .GetRawDataResource(IDR_GET_SALIENT_IMAGE_URL_GEN_JS)
+                .as_string());
+  }
+
+  render_frame_host->ExecuteJavaScriptInIsolatedWorld(
+      get_salient_image_url_script_,
+      base::Bind(
+          &BookmarkImageServiceAndroid::RetrieveSalientImageFromContextCallback,
+          base::Unretained(this), policy, page_url, update_bookmark),
+      chrome::ISOLATED_WORLD_ID_CHROME_INTERNAL);
+}
+
 void BookmarkImageServiceAndroid::RetrieveSalientImageFromContextCallback(
+    blink::WebReferrerPolicy policy,
     const GURL& page_url,
     bool update_bookmark,
     const base::Value* result) {
@@ -181,15 +211,6 @@ void BookmarkImageServiceAndroid::RetrieveSalientImageFromContextCallback(
   dict->GetString("referrerPolicy", &referrerPolicy);
   dict->GetString("imageUrl", &image_url);
 
-  // The policy strings are guaranteed to be in lower-case.
-  blink::WebReferrerPolicy policy = blink::WebReferrerPolicyDefault;
-  if (referrerPolicy == "never")
-    policy = blink::WebReferrerPolicyNever;
-  if (referrerPolicy == "always")
-    policy = blink::WebReferrerPolicyAlways;
-  if (referrerPolicy == "origin")
-    policy = blink::WebReferrerPolicyOrigin;
-
   in_progress_page_urls_.insert(page_url);
 
   Referrer referrer =
diff --git a/chrome/browser/enhanced_bookmarks/android/bookmark_image_service_android.h b/chrome/browser/enhanced_bookmarks/android/bookmark_image_service_android.h
index d44c579..ca47f92 100644
--- a/chrome/browser/enhanced_bookmarks/android/bookmark_image_service_android.h
+++ b/chrome/browser/enhanced_bookmarks/android/bookmark_image_service_android.h
@@ -5,8 +5,9 @@
 #ifndef CHROME_BROWSER_ENHANCED_BOOKMARKS_ANDROID_BOOKMARK_IMAGE_SERVICE_ANDROID_H_
 #define CHROME_BROWSER_ENHANCED_BOOKMARKS_ANDROID_BOOKMARK_IMAGE_SERVICE_ANDROID_H_
 
-#include "components/enhanced_bookmarks/bookmark_image_service.h"
 #include "chrome/browser/bitmap_fetcher/bitmap_fetcher.h"
+#include "components/enhanced_bookmarks/bookmark_image_service.h"
+#include "content/public/common/referrer.h"
 
 namespace chrome {
 class BitmapFetcher;
@@ -35,7 +36,7 @@ class BookmarkImageServiceAndroid : public BookmarkImageService {
   // Searches the current page for a salient image, if a url is found the image
   // is fetched and stored.
   void RetrieveSalientImageFromContext(
-      content::RenderFrameHost* render_frame_host,
+      content::WebContents* web_contents,
       const GURL& page_url,
       bool update_bookmark);
 
@@ -46,15 +47,33 @@ class BookmarkImageServiceAndroid : public BookmarkImageService {
                                       bool update_bookmark);
 
  private:
-  void RetrieveSalientImageFromContextCallback(const GURL& page_url,
+  // The callback for dom_initializer_script_. Once the DOM is initialized,
+  // this method starts execution of get_salient_image_url_script_.
+  void InitializeDomCallback(blink::WebReferrerPolicy policy,
+                             content::RenderFrameHost* render_frame_host,
+                             const GURL& page_url,
+                             bool update_bookmark,
+                             const base::Value* result);
+
+  // The callback for get_salient_image_url_srcipt. Parses the JSON from
+  // execution of get_salient_image_url_script_ to determine the URL for the
+  // salient image and invokes RetrieveSalientImage.
+  void RetrieveSalientImageFromContextCallback(blink::WebReferrerPolicy policy,
+                                               const GURL& page_url,
                                                bool update_bookmark,
                                                const base::Value* result);
 
   scoped_ptr<gfx::Image> ResizeImage(const gfx::Image& image) override;
 
   content::BrowserContext* browser_context_;
+
+  // The script injected in a page to initialize the DOM before extracting image
+  // urls.
+  base::string16 dom_initializer_script_;
+
   // The script injected in a page to extract image urls.
-  base::string16 script_;
+  base::string16 get_salient_image_url_script_;
+
   // Maximum size for retrieved salient images in pixels. This is used when
   // resizing an image.
   gfx::Size max_size_;
diff --git a/chrome/browser/enhanced_bookmarks/android/enhanced_bookmarks_bridge.cc b/chrome/browser/enhanced_bookmarks/android/enhanced_bookmarks_bridge.cc
index 96c2f5b..94a1de1 100644
--- a/chrome/browser/enhanced_bookmarks/android/enhanced_bookmarks_bridge.cc
+++ b/chrome/browser/enhanced_bookmarks/android/enhanced_bookmarks_bridge.cc
@@ -115,7 +115,7 @@ void EnhancedBookmarksBridge::FetchImageForTab(JNIEnv* env,
                                                jobject j_web_contents) {
   WebContents* web_contents = WebContents::FromJavaWebContents(j_web_contents);
   bookmark_image_service_->RetrieveSalientImageFromContext(
-      web_contents->GetMainFrame(), web_contents->GetURL(), true);
+      web_contents, web_contents->GetURL(), true);
 }
 
 ScopedJavaLocalRef<jstring> EnhancedBookmarksBridge::GetBookmarkDescription(
diff --git a/chrome/browser/resources/get_salient_image_url.js b/chrome/browser/resources/get_salient_image_url.js
deleted file mode 100644
index cb3020e..0000000
--- a/chrome/browser/resources/get_salient_image_url.js
+++ /dev/null
@@ -1,67 +0,0 @@
-// 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.
-
-/*
- * Looks on the page to find the image that could be the most representative
- * one.
- */
-(function() {
-  // Extract the referrer policy from the page.
-  var referrerPolicy = 'default';
-  var metaTags = document.getElementsByTagName('meta');
-  for (var i = 0; i < metaTags.length; ++i) {
-    if (metaTags[i].name.toLowerCase() == 'referrer') {
-      referrerPolicy = metaTags[i].content.toLowerCase();
-      break;
-    }
-  }
-
-  // See what to use for JSON. Some pages use a library that overrides JSON.
-  var jsonEncoder = JSON.stringify;
-  if (!jsonEncoder)
-    jsonEncoder = JSON.encode;
-
-  // First look if there is an Open Graph Image property available.
-  var ogImage = document.querySelector('meta[property=\"og:image\"]');
-  if (ogImage) {
-    // Checks that the url in ogImage has a path that contains more than just a
-    // simple '/'.
-    var url = ogImage.content;
-    var location = document.createElement('a');
-    location.href = url;
-    if (location.pathname.length > 1) {
-      return jsonEncoder({
-        'imageUrl': url,
-        'referrerPolicy': referrerPolicy
-      });
-    }
-  }
-
-  // Iterates through the images on the page, find the largest one that doesn't
-  // look like a banner.
-  var maxPointSize = 0;
-  var maxImage = null;
-
-  var images = document.getElementsByTagName('img');
-  for (var i = 0; i < images.length; i++) {
-    var currentImage = images[i];
-    var aspectRatio = currentImage.width / currentImage.height;
-    if (aspectRatio >= 2.4 || aspectRatio <= 0.5)
-      continue;  // Skip weirdly shaped images. Those are ads or headers.
-    var pointSize = currentImage.width * currentImage.height;
-    if (pointSize > maxPointSize) {
-      maxPointSize = pointSize;
-      maxImage = currentImage;
-    }
-  }
-
-  // Only keep images larger than 320*160.
-  if (maxPointSize <= 51200.0 || maxImage === null)
-    return '';
-
-  return jsonEncoder({
-    'imageUrl': maxImage.src,
-    'referrerPolicy': referrerPolicy
-  });
-})();
diff --git a/chrome/chrome_browser.gypi b/chrome/chrome_browser.gypi
index ad5b486..c4bac94 100644
--- a/chrome/chrome_browser.gypi
+++ b/chrome/chrome_browser.gypi
@@ -1318,6 +1318,14 @@
       'browser/bookmarks/chrome_bookmark_client_factory.h',
       'browser/bookmarks/enhanced_bookmarks_features.cc',
       'browser/bookmarks/enhanced_bookmarks_features.h',
+      'browser/enhanced_bookmarks/chrome_bookmark_server_cluster_service.cc',
+      'browser/enhanced_bookmarks/chrome_bookmark_server_cluster_service.h',
+      'browser/enhanced_bookmarks/chrome_bookmark_server_cluster_service_factory.cc',
+      'browser/enhanced_bookmarks/chrome_bookmark_server_cluster_service_factory.h',
+      'browser/enhanced_bookmarks/enhanced_bookmark_model_factory.cc',
+      'browser/enhanced_bookmarks/enhanced_bookmark_model_factory.h',
+    ],
+    'chrome_browser_bookmark_android_sources': [
       'browser/enhanced_bookmarks/android/bookmark_image_service_android.cc',
       'browser/enhanced_bookmarks/android/bookmark_image_service_android.h',
       'browser/enhanced_bookmarks/android/bookmark_image_service_factory.cc',
@@ -1326,12 +1334,6 @@
       'browser/enhanced_bookmarks/android/enhanced_bookmark_tab_helper.h',
       'browser/enhanced_bookmarks/android/enhanced_bookmarks_bridge.cc',
       'browser/enhanced_bookmarks/android/enhanced_bookmarks_bridge.h',
-      'browser/enhanced_bookmarks/chrome_bookmark_server_cluster_service.cc',
-      'browser/enhanced_bookmarks/chrome_bookmark_server_cluster_service.h',
-      'browser/enhanced_bookmarks/chrome_bookmark_server_cluster_service_factory.cc',
-      'browser/enhanced_bookmarks/chrome_bookmark_server_cluster_service_factory.h',
-      'browser/enhanced_bookmarks/enhanced_bookmark_model_factory.cc',
-      'browser/enhanced_bookmarks/enhanced_bookmark_model_factory.h',
     ],
     'chrome_browser_browser_process_sources': [
       'browser/browser_process.cc',
@@ -3584,6 +3586,8 @@
             '../components/components.gyp:service_tab_launcher',
             '../components/components.gyp:web_contents_delegate_android',
             '../components/components_resources.gyp:components_resources',
+            '../components/resources/enhanced_bookmarks/enhanced_bookmarks.gypi:*',
+            '../components/resources/enhanced_bookmarks/enhanced_bookmarks_resources.gyp:*',
             '../third_party/android_opengl/etc1/etc1.gyp:etc1',
             '../third_party/libaddressinput/libaddressinput.gyp:libaddressinput_util',
             'chrome_browser_jni_headers',
@@ -3595,7 +3599,10 @@
             '../components/components.gyp:web_modal',
             '../third_party/libaddressinput/libaddressinput.gyp:libaddressinput',
           ],
-          'sources': [ '<@(chrome_browser_android_sources)' ],
+          'sources': [
+            '<@(chrome_browser_android_sources)',
+            '<@(chrome_browser_bookmark_android_sources)',
+           ],
           'defines': [ 'ENABLE_DATA_REDUCTION_PROXY_DEBUGGING' ],
           'conditions': [
             ['use_seccomp_bpf==1', {
diff --git a/chrome/chrome_repack_resources.gypi b/chrome/chrome_repack_resources.gypi
index 8c0c7e7..9b06ec6 100644
--- a/chrome/chrome_repack_resources.gypi
+++ b/chrome/chrome_repack_resources.gypi
@@ -28,6 +28,11 @@
           '<(SHARED_INTERMEDIATE_DIR)/ui/oobe/oobe_resources.pak',
         ],
       }],
+      ['OS == "android"', {
+        'pak_inputs': [
+          '<(SHARED_INTERMEDIATE_DIR)/components/resources/enhanced_bookmarks/enhanced_bookmarks_resources.pak',
+        ]
+      }],
       ['OS != "ios"', {
         'pak_inputs': [
           '<(SHARED_INTERMEDIATE_DIR)/blink/public/resources/blink_resources.pak',
diff --git a/components/resources/enhanced_bookmarks/OWNERS b/components/resources/enhanced_bookmarks/OWNERS
new file mode 100644
index 0000000..ffa7f07
--- /dev/null
+++ b/components/resources/enhanced_bookmarks/OWNERS
@@ -0,0 +1,3 @@
+kkimlabs@chromium.org
+noyau@chromium.org
+twellington@chromium.org
diff --git a/components/resources/enhanced_bookmarks/dom_initializer.js b/components/resources/enhanced_bookmarks/dom_initializer.js
new file mode 100644
index 0000000..8f8d4e8
--- /dev/null
+++ b/components/resources/enhanced_bookmarks/dom_initializer.js
@@ -0,0 +1,11 @@
+// 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.
+
+goog.provide('DomInitializer');
+
+goog.require('image.collections.extension.domextractor.DomController');
+
+var domController =
+    new image.collections.extension.domextractor.DomController();
+domController.initialize();
diff --git a/components/resources/enhanced_bookmarks/enhanced_bookmarks.gypi b/components/resources/enhanced_bookmarks/enhanced_bookmarks.gypi
new file mode 100644
index 0000000..f9dcb67
--- /dev/null
+++ b/components/resources/enhanced_bookmarks/enhanced_bookmarks.gypi
@@ -0,0 +1,89 @@
+# 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.
+{
+  'targets' :[
+    {
+      'target_name': 'document_image_extractor',
+      'type': 'none',
+      'variables': { 'CLOSURE_DIR': '<(DEPTH)/third_party/closure_compiler', },
+      'actions': [
+        {
+          # This action optionally takes these arguments:
+          # - depends: scripts that the source file depends on being included already
+          # - externs: files that describe globals used by |source|
+          'action_name': 'Compile enhanced bookmarks image extractor JavaScript',
+          'variables': {
+            'source_file': 'get_salient_image_url.js',
+            'out_file': '<(SHARED_INTERMEDIATE_DIR)/closure/<!(python <(CLOSURE_DIR)/build/outputs.py <@(source_file))',
+          },
+          'inputs': [
+            '<(CLOSURE_DIR)/compile.py',
+            '<(CLOSURE_DIR)/processor.py',
+            '<(CLOSURE_DIR)/build/inputs.py',
+            '<(CLOSURE_DIR)/build/outputs.py',
+            '<(CLOSURE_DIR)/compiler/compiler.jar',
+            '<(CLOSURE_DIR)/runner/runner.jar',
+            '<!@(python <(CLOSURE_DIR)/build/inputs.py <(source_file))',
+          ],
+          'outputs': [
+            '<(out_file)',
+          ],
+          'action': [
+            'python',
+            '<(CLOSURE_DIR)/compile.py',
+            '<@(document_image_extractor_js_files)',
+            '<(source_file)',
+            '--out_file', '<(out_file)',
+            '--no-single-file',
+            '--output_wrapper', '(function(){%output% return GetSalientImageUrl();})();',
+          ],
+        }
+      ],
+      'includes': [
+        '../../../third_party/document_image_extractor/document_image_extractor_files.gypi'
+      ],
+    },
+    {
+      'target_name': 'dom_initializer',
+      'type': 'none',
+      'variables': { 'CLOSURE_DIR': '<(DEPTH)/third_party/closure_compiler', },
+      'actions': [
+        {
+          # This action optionally takes these arguments:
+          # - depends: scripts that the source file depends on being included already
+          # - externs: files that describe globals used by |source|
+          'action_name': 'Compile enhanced bookmarks dom initializer JavaScript',
+          'variables': {
+            'source_file': 'dom_initializer.js',
+            'out_file': '<(SHARED_INTERMEDIATE_DIR)/closure/<!(python <(CLOSURE_DIR)/build/outputs.py <@(source_file))',
+          },
+          'inputs': [
+            '<(CLOSURE_DIR)/compile.py',
+            '<(CLOSURE_DIR)/processor.py',
+            '<(CLOSURE_DIR)/build/inputs.py',
+            '<(CLOSURE_DIR)/build/outputs.py',
+            '<(CLOSURE_DIR)/compiler/compiler.jar',
+            '<(CLOSURE_DIR)/runner/runner.jar',
+            '<!@(python <(CLOSURE_DIR)/build/inputs.py <(source_file))',
+          ],
+          'outputs': [
+            '<(out_file)',
+          ],
+          'action': [
+            'python',
+            '<(CLOSURE_DIR)/compile.py',
+            '<@(dom_controller_js_files)',
+            '<(source_file)',
+            '--out_file', '<(out_file)',
+            '--no-single-file',
+            '--output_wrapper', '(function(){%output%})();',
+          ]
+        }
+      ],
+      'includes': [
+        '../../../third_party/document_image_extractor/dom_controller_files.gypi'
+      ],
+    },
+  ],
+}
diff --git a/components/resources/enhanced_bookmarks/enhanced_bookmarks_resources.grd b/components/resources/enhanced_bookmarks/enhanced_bookmarks_resources.grd
new file mode 100644
index 0000000..6fa24e6
--- /dev/null
+++ b/components/resources/enhanced_bookmarks/enhanced_bookmarks_resources.grd
@@ -0,0 +1,15 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<grit latest_public_release="0" current_release="1">
+  <outputs>
+    <output filename="grit/enhanced_bookmarks_resources.h" type="rc_header">
+      <emit emit_type='prepend'></emit>
+    </output>
+    <output filename="enhanced_bookmarks_resources.pak" type="data_package" />
+  </outputs>
+  <release seq="1">
+    <includes>
+      <include name="IDR_GET_SALIENT_IMAGE_URL_GEN_JS" file="${get_salient_image_url_gen_js}" use_base_dir="false" type="BINDATA" />
+      <include name="IDR_DOM_INITIALIZER_GEN_JS" file="${dom_initializer_gen_js}" use_base_dir="false" type="BINDATA" />
+    </includes>
+  </release>
+</grit>
diff --git a/components/resources/enhanced_bookmarks/enhanced_bookmarks_resources.gyp b/components/resources/enhanced_bookmarks/enhanced_bookmarks_resources.gyp
new file mode 100644
index 0000000..c0c817d
--- /dev/null
+++ b/components/resources/enhanced_bookmarks/enhanced_bookmarks_resources.gyp
@@ -0,0 +1,31 @@
+# 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.
+
+{
+  'targets': [
+    {
+      'target_name': 'enhanced_bookmarks_resources',
+      'type': 'none',
+      'variables': {
+        'grit_out_dir': '<(SHARED_INTERMEDIATE_DIR)/components/resources/enhanced_bookmarks',
+        'get_salient_image_url_gen_js': '<(SHARED_INTERMEDIATE_DIR)/closure/components/resources/enhanced_bookmarks/get_salient_image_url.js',
+        'dom_initializer_gen_js': '<(SHARED_INTERMEDIATE_DIR)/closure/components/resources/enhanced_bookmarks/dom_initializer.js',
+      },
+      'actions': [
+        {
+          'action_name': 'generate_enhanced_bookmarks_resources',
+          'variables': {
+            'grit_grd_file': 'enhanced_bookmarks_resources.grd',
+            'grit_additional_defines': [
+              '-E', 'get_salient_image_url_gen_js=<(get_salient_image_url_gen_js)',
+              '-E', 'dom_initializer_gen_js=<(dom_initializer_gen_js)',
+            ],
+          },
+          'includes': [ '../../../build/grit_action.gypi' ],
+        },
+      ],
+      'includes': [ '../../../build/grit_target.gypi' ],
+    },
+  ],
+}
diff --git a/components/resources/enhanced_bookmarks/get_salient_image_url.js b/components/resources/enhanced_bookmarks/get_salient_image_url.js
new file mode 100644
index 0000000..c7a32b6
--- /dev/null
+++ b/components/resources/enhanced_bookmarks/get_salient_image_url.js
@@ -0,0 +1,59 @@
+// 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.
+
+goog.require('image.collections.extension.domextractor.DocumentImageExtractor');
+
+/*
+ * Examines the DOM to find the image that is the most representative of the
+ * webpage.
+ */
+var GetSalientImageUrl = function() {
+  // Extract the referrer policy from the page.
+  var referrerPolicy = 'default';
+  var metaTags = document.getElementsByTagName('meta');
+  for (var i = 0; i < metaTags.length; i++) {
+    if (metaTags[i].name.toLowerCase() == 'referrer') {
+      referrerPolicy = metaTags[i].content.toLowerCase();
+      break;
+    }
+  }
+
+  // Determine which JSON method (stringify or encode) to use for encoding.
+  // Some pages use a library that overrides JSON, so JSON['stringify'] is not
+  // always available.
+  var jsonEncoder = JSON['stringify'];
+  if (!jsonEncoder)
+    jsonEncoder = JSON['encode'];
+
+  var context = new
+      image.collections.extension.domextractor.DocumentImageExtractor.Context();
+  var documentImageExtractor =
+      new image.collections.extension.domextractor.DocumentImageExtractor();
+  var images = documentImageExtractor.extractFromNodeList(
+      document.querySelectorAll('img,link,meta'), context);
+
+  var maxImage = null;
+  var maxRelevance = 0;
+  for (var i = 0; i < images.length; i++) {
+    var currentImage = images[i];
+    var imageSize = currentImage.getSize();
+    if (!imageSize)
+      continue;
+
+    if (currentImage.getRelevance() > maxRelevance) {
+      maxImage = currentImage;
+      maxRelevance = currentImage.getRelevance();
+    }
+  }
+
+  if (maxImage === null)
+    return '';
+
+  var result = jsonEncoder({
+    'imageUrl': maxImage.getUrl(),
+    'referrerPolicy': referrerPolicy
+  });
+
+  return result;
+};
diff --git a/tools/gritsettings/resource_ids b/tools/gritsettings/resource_ids
index 6562e14..7cd7d64 100644
--- a/tools/gritsettings/resource_ids
+++ b/tools/gritsettings/resource_ids
@@ -248,6 +248,9 @@
   "components/resources/components_scaled_resources.grd": {
     "structures": [30280],
   },
+  "components/resources/enhanced_bookmarks/enhanced_bookmarks_resources.grd": {
+    "includes": [30330],
+  },
   "third_party/WebKit/public/blink_resources.grd": {
     "includes": [30350],
     "structures": [30650],