Upstream oodles of Chrome for Android code into Chromium.

chrome/android/java_staging/src/org/chromium/chrome/browser/contextualsearch/ContextualSearchObservable.java

+// 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.
+
+package org.chromium.chrome.browser.contextualsearch;
+
+import org.chromium.base.ObserverList;
+import org.chromium.chrome.browser.ChromeActivity;
+import org.chromium.chrome.browser.gsa.GSAContextDisplaySelection;
+import org.chromium.content.browser.ContentViewCore;
+
+import java.net.URL;
+
+import javax.annotation.Nullable;
+
+
+/**
+ * Provides observers for the Contextual Search Manager.
+ */
+public class ContextualSearchObservable {
+
+    protected final ContextualSearchPolicy mPolicy;
+
+    private final ObserverList<ContextualSearchObserver> mObservers =
+            new ObserverList<ContextualSearchObserver>();
+
+
+    ContextualSearchObservable(ChromeActivity activity) {
+        mPolicy = ContextualSearchPolicy.getInstance(activity);
+    }
+
+    /**
+     * @param observer The observer to notify when the user performs a contextual search.
+     */
+    public void addObserver(ContextualSearchObserver observer) {
+        mObservers.addObserver(observer);
+    }
+
+    /**
+     * @param observer The observer to no longer notify when the user performs a contextual search.
+     */
+    public void removeObserver(ContextualSearchObserver observer) {
+        mObservers.removeObserver(observer);
+    }
+
+    /**
+     * Notifies all Contextual Search observers that a search has occurred.
+     * @param selectionContext The selection and context that triggered the search.
+     * @param baseContentViewUrl The {@link ContentViewCore} of the base page.
+     */
+    protected void notifyShowContextualSearch(GSAContextDisplaySelection selectionContext,
+            @Nullable URL baseContentViewUrl) {
+        if (!mPolicy.canSendSurroundings(baseContentViewUrl)) selectionContext = null;
+
+        for (ContextualSearchObserver observer : mObservers) {
+            observer.onShowContextualSearch(selectionContext);
+        }
+    }
+
+    /**
+     * Notifies all Contextual Search observers that a search ended and is no longer in effect.
+     */
+    protected void notifyHideContextualSearch() {
+        for (ContextualSearchObserver observer : mObservers) {
+            observer.onHideContextualSearch();
+        }
+    }
+}