[Android][Mac] Enable spellcheck caching on Android and Mac platforms.

components/spellcheck/renderer/spellcheck_provider.cc

 // Copyright (c) 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 "components/spellcheck/renderer/spellcheck_provider.h"
 
 #include "base/command_line.h"
 #include "base/metrics/histogram_macros.h"
 #include "components/spellcheck/common/spellcheck_marker.h"
 #include "components/spellcheck/common/spellcheck_messages.h"
@@ skipping 242 matching lines @@
     return;
   text_check_completions_.Remove(identifier);
   blink::WebVector<blink::WebTextCheckingResult> textcheck_results;
   spellcheck_->CreateTextCheckingResults(SpellCheck::DO_NOT_MODIFY,
                                          0,
                                          line,
                                          results,
                                          &textcheck_results);
   completion->didFinishCheckingText(textcheck_results);
 
-  // TODO(groby): Add request caching once OSX reports back original request.
-  // (cf. SpellCheckProvider::OnRespondSpellingService)
   // Cache the request and the converted results.
+  last_request_ = line;

[groby-ooo-7-16, 2016/09/09 22:41:38]

Did you verify OSX actually returns the original request? Quick glance at the
code seems to confirm that, but I've not looked in depth.

[timvolodine, 2016/09/12 15:31:39]

Yes, tested this on Mac OS X, it does return the "line" properly, and caching
appears to work.

+  last_results_.swap(textcheck_results);
 }
 
 void SpellCheckProvider::OnToggleSpellPanel(bool is_currently_visible) {
   if (!render_view()->GetWebView())
     return;
   // We need to tell the webView whether the spelling panel is visible or not so
   // that it won't need to make ipc calls later.
   spelling_panel_visible_ = is_currently_visible;
   render_view()->GetWebView()->focusedFrame()->executeCommand(
       WebString::fromUTF8("ToggleSpellPanel"));
@@ skipping 65 matching lines @@
       return true;
     }
   }
 
   return false;
 }
 
 void SpellCheckProvider::OnDestruct() {
   delete this;
 }