Adds selection expansion support for Contextual Search.

content/renderer/render_frame_impl.cc

 // Copyright 2013 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/renderer/render_frame_impl.h"
 
 #include <map>
 #include <string>
 
 #include "base/auto_reset.h"
@@ skipping 995 matching lines @@
                         OnCustomContextMenuAction)
     IPC_MESSAGE_HANDLER(InputMsg_Undo, OnUndo)
     IPC_MESSAGE_HANDLER(InputMsg_Redo, OnRedo)
     IPC_MESSAGE_HANDLER(InputMsg_Cut, OnCut)
     IPC_MESSAGE_HANDLER(InputMsg_Copy, OnCopy)
     IPC_MESSAGE_HANDLER(InputMsg_Paste, OnPaste)
     IPC_MESSAGE_HANDLER(InputMsg_PasteAndMatchStyle, OnPasteAndMatchStyle)
     IPC_MESSAGE_HANDLER(InputMsg_Delete, OnDelete)
     IPC_MESSAGE_HANDLER(InputMsg_SelectAll, OnSelectAll)
     IPC_MESSAGE_HANDLER(InputMsg_SelectRange, OnSelectRange)
+    IPC_MESSAGE_HANDLER(InputMsg_AdjustSelectionByCharacterOffset,
+                        OnAdjustSelectionByCharacterOffset)
     IPC_MESSAGE_HANDLER(InputMsg_Unselect, OnUnselect)
     IPC_MESSAGE_HANDLER(InputMsg_MoveRangeSelectionExtent,
                         OnMoveRangeSelectionExtent)
     IPC_MESSAGE_HANDLER(InputMsg_Replace, OnReplace)
     IPC_MESSAGE_HANDLER(InputMsg_ReplaceMisspelling, OnReplaceMisspelling)
     IPC_MESSAGE_HANDLER(InputMsg_ExtendSelectionAndDelete,
                         OnExtendSelectionAndDelete)
     IPC_MESSAGE_HANDLER(InputMsg_SetCompositionFromExistingText,
                         OnSetCompositionFromExistingText)
     IPC_MESSAGE_HANDLER(InputMsg_ExecuteNoValueEditCommand,
@@ skipping 293 matching lines @@
 
 void RenderFrameImpl::OnSelectRange(const gfx::Point& base,
                                     const gfx::Point& extent) {
   // This IPC is dispatched by RenderWidgetHost, so use its routing id.
   Send(new InputHostMsg_SelectRange_ACK(GetRenderWidget()->routing_id()));
 
   base::AutoReset<bool> handling_select_range(&handling_select_range_, true);
   frame_->selectRange(base, extent);
 }
 
+void RenderFrameImpl::OnAdjustSelectionByCharacterOffset(int start_adjust,
+                                                         int end_adjust) {
+  size_t start, length;
+  if (!GetRenderWidget()->webwidget()->caretOrSelectionRange(
+      &start, &length)) {
+    return;
+  }
+
+  // Sanity checks to disallow empty and out of range selections.
+  if (start_adjust - end_adjust > static_cast<int>(length)
+      || static_cast<int>(start) + start_adjust < 0) {
+    return;
+  }
+
+  // A negative adjust amount moves the selection towards the beginning of
+  // the document, a positive amount moves the selection towards the end of
+  // the document.
+  start += start_adjust;
+  length += end_adjust - start_adjust;
+
+  frame_->selectRange(WebRange::fromDocumentRange(frame_, start, length));
+}
+
 void RenderFrameImpl::OnUnselect() {
   base::AutoReset<bool> handling_select_range(&handling_select_range_, true);
   frame_->executeCommand(WebString::fromUTF8("Unselect"), GetFocusedElement());
 }
 
 void RenderFrameImpl::OnMoveRangeSelectionExtent(const gfx::Point& point) {
   // This IPC is dispatched by RenderWidgetHost, so use its routing id.
   Send(new InputHostMsg_MoveRangeSelectionExtent_ACK(
       GetRenderWidget()->routing_id()));
 
@@ skipping 3683 matching lines @@
 void RenderFrameImpl::RegisterMojoServices() {
   // Only main frame have ImageDownloader service.
   if (!frame_->parent()) {
     GetServiceRegistry()->AddService<image_downloader::ImageDownloader>(
         base::Bind(&ImageDownloaderImpl::CreateMojoService,
                    base::Unretained(this)));
   }
 }
 
 }  // namespace content