Create a spellcheck component that will allow any embedder to reuse common functionality.

chrome/renderer/spellchecker/spellcheck.h

Index: chrome/renderer/spellchecker/spellcheck.h
diff --git a/chrome/renderer/spellchecker/spellcheck.h b/chrome/renderer/spellchecker/spellcheck.h
index a623d563fd23c74b4e3ac53419ce1a92457c6bea..6c372f7456fc55949393f4d548379bf814e465a5 100644
--- a/chrome/renderer/spellchecker/spellcheck.h
+++ b/chrome/renderer/spellchecker/spellcheck.h
@@ -19,9 +19,13 @@
 #include "chrome/renderer/spellchecker/custom_dictionary_engine.h"
 #include "content/public/renderer/render_process_observer.h"
 
-struct SpellCheckBDictLanguage;
+
 class SpellcheckLanguage;
+
+namespace spellcheck {
+struct SpellCheckBDictLanguage;
 struct SpellCheckResult;
+}
 
 namespace blink {
 class WebTextCheckingCompletion;
@@ -102,7 +106,7 @@ class SpellCheck : public content::RenderProcessObserver,
       ResultFilter filter,
       int line_offset,
       const base::string16& line_text,
-      const std::vector<SpellCheckResult>& spellcheck_results,
+      const std::vector<spellcheck::SpellCheckResult>& spellcheck_results,
       blink::WebVector<blink::WebTextCheckingResult>* textcheck_results);
 
   bool IsSpellcheckEnabled();
@@ -125,8 +129,9 @@ class SpellCheck : public content::RenderProcessObserver,
    bool OnControlMessageReceived(const IPC::Message& message) override;
 
   // Message handlers.
-   void OnInit(const std::vector<SpellCheckBDictLanguage>& bdict_languages,
-               const std::set<std::string>& custom_words);
+   void OnInit(
+       const std::vector<spellcheck::SpellCheckBDictLanguage>& bdict_languages,
+       const std::set<std::string>& custom_words);
    void OnCustomDictionaryChanged(const std::set<std::string>& words_added,
                                   const std::set<std::string>& words_removed);
   void OnEnableSpellCheck(bool enable);