Add spell checking support (issue #137).

This includes:
- Red underline of misspelled words in html text areas.
- Right-click context menu options to correct the misspelled word.
- New CefBrowser::ReplaceMisspelling method for accepting a word replacement.
- Methods added to CefContextMenuParams for retrieving spelling-related information.
- Uses the unified text checker when auto-correct is not enabled to match Google Chrome behavior.
- On Windows and Linux a hunspell dictionary file will be downloaded to the "<cache_path>/Dictionaries" directory as needed, or used from the <cache_path> directory if the file already exists there. The dictionary file will be downloaded from http://cache.pack.google.com/edgedl/chrome/dict/<LANG>-3-0.bdic where <LANG> is the language abbreviation.
- On OS X the spell checking implementation will use the system NSSpellChecker implementation.

The following command-line flags have been added:
--disable-spell-checking => Disable spell-checking support (no red underline, no dictionary file download, etc).
--enable-spelling-auto-correct => Automatically correct common misspellings while typing (like 'omre' to 'more' on Windows/Linux or 'ehlo' to 'helo' on OS X).
--enable-spelling-service => Enable use of the remote Google spelling service (this requires Google API keys).
--override-spell-check-lang=<LANG> => Use the specified dictionary language <LANG> instead of the language specified in the locales.pak file. To see the default/supported dictionary languages: https://code.google.com/p/chromium/codesearch#search/&q=IDS_SPELLCHECK_DICTIONARY%20xtb&sq=package:chromium


git-svn-id: https://chromiumembedded.googlecode.com/svn/trunk@1859 5089003a-bbd8-11dd-ad1f-f1f9622dbc98

libcef/browser/context_menu_params_impl.cc

@@ -95,11 +95,44 @@ CefString CefContextMenuParamsImpl::GetSelectionText() {
   return const_value().selection_text;
 }
 
+CefString CefContextMenuParamsImpl::GetMisspelledWord() {
+  CEF_VALUE_VERIFY_RETURN(false, CefString());
+  return const_value().misspelled_word;
+}
+
+int CefContextMenuParamsImpl::GetMisspellingHash() {
+  CEF_VALUE_VERIFY_RETURN(false, 0);
+  return const_value().misspelling_hash;
+}
+
+bool CefContextMenuParamsImpl::GetDictionarySuggestions(
+    std::vector<CefString>& suggestions) {
+  CEF_VALUE_VERIFY_RETURN(false, false);
+
+  if (!suggestions.empty())
+    suggestions.clear();
+
+  if(const_value().dictionary_suggestions.empty())
+    return false;
+
+  std::vector<base::string16>::const_iterator it =
+      const_value().dictionary_suggestions.begin();
+  for (; it != const_value().dictionary_suggestions.end(); ++it)
+    suggestions.push_back(*it);
+
+  return true;
+}
+
 bool CefContextMenuParamsImpl::IsEditable() {
   CEF_VALUE_VERIFY_RETURN(false, false);
   return const_value().is_editable;
 }
 
+bool CefContextMenuParamsImpl::IsSpellCheckEnabled() {
+  CEF_VALUE_VERIFY_RETURN(false, false);
+  return const_value().spellcheck_enabled;
+}
+
 CefContextMenuParamsImpl::EditStateFlags
     CefContextMenuParamsImpl::GetEditStateFlags() {
   CEF_VALUE_VERIFY_RETURN(false, CM_EDITFLAG_NONE);