Add an interface to gather text surrounding the selection.

content/browser/android/content_view_core_impl.cc

 // Copyright 2012 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.
 
 #include "content/browser/android/content_view_core_impl.h"
 
 #include "base/android/jni_android.h"
 #include "base/android/jni_array.h"
 #include "base/android/jni_string.h"
 #include "base/android/scoped_java_ref.h"
@@ skipping 19 matching lines @@
 #include "content/browser/renderer_host/input/web_input_event_builders_android.h"
 #include "content/browser/renderer_host/input/web_input_event_util.h"
 #include "content/browser/renderer_host/java/java_bound_object.h"
 #include "content/browser/renderer_host/java/java_bridge_dispatcher_host_manager.h"
 #include "content/browser/renderer_host/render_view_host_impl.h"
 #include "content/browser/renderer_host/render_widget_host_impl.h"
 #include "content/browser/renderer_host/render_widget_host_view_android.h"
 #include "content/browser/screen_orientation/screen_orientation_dispatcher_host.h"
 #include "content/browser/ssl/ssl_host_state.h"
 #include "content/browser/web_contents/web_contents_view_android.h"
+#include "content/common/frame_messages.h"
 #include "content/common/input/web_input_event_traits.h"
 #include "content/common/input_messages.h"
 #include "content/common/view_messages.h"
 #include "content/public/browser/browser_accessibility_state.h"
 #include "content/public/browser/browser_context.h"
 #include "content/public/browser/favicon_status.h"
 #include "content/public/browser/render_frame_host.h"
 #include "content/public/browser/web_contents.h"
 #include "content/public/common/content_client.h"
 #include "content/public/common/content_switches.h"
@@ skipping 1481 matching lines @@
     // If it was actually enabled globally, enable it for this RenderWidget now.
     if (accessibility_state->IsAccessibleBrowser() && host_impl)
       host_impl->AddAccessibilityMode(AccessibilityModeComplete);
   } else {
     accessibility_state->ResetAccessibilityMode();
     if (host_impl)
       host_impl->ResetAccessibilityMode();
   }
 }
 
+void ContentViewCoreImpl::OnTextSurroundingSelectionResponse(
+    const base::string16& content,
+    int start_offset,
+    int end_offset) {
+  if (text_surroundings_callback_.is_null())
+    return;
+  text_surroundings_callback_.Run(content, start_offset, end_offset);
+  // The callback should be run only once, since it's tied to the request.
+  // Set to the default constructor so an is_null test can prevent a re-run.
+  text_surroundings_callback_ = TextSurroundingSelectionCallback();

[Ted C, 2014/06/19 21:05:12]

could this also be .Reset() instead of constructing a new one?

[donnd, 2014/06/19 21:27:24]

Done.

+}
+
 void ContentViewCoreImpl::SendOrientationChangeEventInternal() {
   RenderWidgetHostViewAndroid* rwhv = GetRenderWidgetHostViewAndroid();
   if (rwhv)
     rwhv->UpdateScreenInfo(GetViewAndroid());
 
   // TODO(mlamouri): temporary plumbing for Screen Orientation, this will change
   // in the future. The OnResize IPC message sent from UpdateScreenInfo() will
   // propagate the information.
   blink::WebScreenOrientationType orientation =
       blink::WebScreenOrientationPortraitPrimary;
@@ skipping 46 matching lines @@
   return GetRenderProcessIdFromRenderViewHost(
       web_contents_->GetRenderViewHost());
 }
 
 void ContentViewCoreImpl::SetBackgroundOpaque(JNIEnv* env, jobject jobj,
     jboolean opaque) {
   if (GetRenderWidgetHostViewAndroid())
     GetRenderWidgetHostViewAndroid()->SetBackgroundOpaque(opaque);
 }
 
+void ContentViewCoreImpl::RequestTextSurroundingSelection(
+    int max_length,
+    const TextSurroundingSelectionCallback& callback) {
+  DCHECK(!callback.is_null());
+  RenderFrameHost* focused_frame = web_contents_->GetFocusedFrame();
+  if (!focused_frame)
+    return;
+  // Only one outstanding request is allowed at any given time.
+  DCHECK(text_surroundings_callback_.is_null());
+  // TODO(donnd): consider storing the callback in RenderWidgetHostViewAndroid,

[Donn Denman, 2014/06/19 14:24:29]

Ted, we're particularly interested in your opinion of this lifetime issue is,
and if you have other suggestions.

[Ted C, 2014/06/19 21:05:12]

Per the offline discussion, I think it is safer to just have the callback be
owned by the RenderWidgetHostViewAndroid.  Then it will get killed on renderer
crashes or when swapping due to a navigation.  I think it's a bit odd to go
through the frame host and then back out through the render_widget_host_view,
but that isn't something for this change.

[donnd, 2014/06/19 21:27:24]

Done.

+  // and clear it when we change the ContentViewCore or if the renderer crashes.
+  // See crbug.com/386434 for details.
+  text_surroundings_callback_ = callback;
+  focused_frame->Send(new FrameMsg_TextSurroundingSelectionRequest(
+      focused_frame->GetRoutingID(), max_length));
+}
+
 void ContentViewCoreImpl::OnSmartClipDataExtracted(
     const base::string16& result) {
   JNIEnv* env = AttachCurrentThread();
   ScopedJavaLocalRef<jobject> obj = java_ref_.get(env);
   if (obj.is_null())
     return;
   ScopedJavaLocalRef<jstring> jresult = ConvertUTF16ToJavaString(env, result);
   Java_ContentViewCore_onSmartClipDataExtracted(
       env, obj.obj(), jresult.obj());
 }
@@ skipping 19 matching lines @@
       reinterpret_cast<ui::WindowAndroid*>(window_android),
       retained_objects_set);
   return reinterpret_cast<intptr_t>(view);
 }
 
 bool RegisterContentViewCore(JNIEnv* env) {
   return RegisterNativesImpl(env);
 }
 
 }  // namespace content