Make SpellCheckPanel compiled and used only on Mac

components/spellcheck/common/spellcheck_messages.h

Index: components/spellcheck/common/spellcheck_messages.h
diff --git a/components/spellcheck/common/spellcheck_messages.h b/components/spellcheck/common/spellcheck_messages.h
index b31cf56496963b2776bef3bec23d89f985624330..c36a6c83e9b13031eb1e7914d07c4c0956f1ead8 100644
--- a/components/spellcheck/common/spellcheck_messages.h
+++ b/components/spellcheck/common/spellcheck_messages.h
@@ -63,16 +63,18 @@ IPC_MESSAGE_ROUTED4(SpellCheckMsg_RespondSpellingService,
 #endif
 
 #if BUILDFLAG(USE_BROWSER_SPELLCHECKER)
-// This message tells the renderer to advance to the next misspelling. It is
-// sent when the user clicks the "Find Next" button on the spelling panel.
-IPC_MESSAGE_ROUTED0(SpellCheckMsg_AdvanceToNextMisspelling)
-
 // Sends when NSSpellChecker finishes checking text received by a preceding
 // SpellCheckHostMsg_RequestTextCheck message.
 IPC_MESSAGE_ROUTED3(SpellCheckMsg_RespondTextCheck,
                     int /* request identifier given by WebKit */,
                     base::string16 /* sentence */,
                     std::vector<SpellCheckResult>)
+#endif
+
+#if BUILDFLAG(HAS_SPELLCHECK_PANEL)
+// This message tells the renderer to advance to the next misspelling. It is
+// sent when the user clicks the "Find Next" button on the spelling panel.
+IPC_MESSAGE_ROUTED0(SpellCheckMsg_AdvanceToNextMisspelling)
 
 IPC_MESSAGE_ROUTED1(SpellCheckMsg_ToggleSpellPanel, bool)
 #endif
@@ -100,14 +102,6 @@ IPC_MESSAGE_CONTROL3(SpellCheckHostMsg_CallSpellingService,
 #endif
 
 #if BUILDFLAG(USE_BROWSER_SPELLCHECKER)
-// Tells the browser to display or not display the SpellingPanel
-IPC_MESSAGE_ROUTED1(SpellCheckHostMsg_ShowSpellingPanel,
-                    bool /* if true, then show it, otherwise hide it*/)
-
-// Tells the browser to update the spelling panel with the given word.
-IPC_MESSAGE_ROUTED1(SpellCheckHostMsg_UpdateSpellingPanelWithMisspelledWord,
-                    base::string16 /* the word to update the panel with */)
-
 // TODO(groby): This needs to originate from SpellcheckProvider.
 IPC_SYNC_MESSAGE_CONTROL2_1(SpellCheckHostMsg_CheckSpelling,
                             base::string16 /* word */,
@@ -127,3 +121,13 @@ IPC_MESSAGE_ROUTED2(SpellCheckHostMsg_ToggleSpellCheck,
                     bool /* enabled */,
                     bool /* checked */)
 #endif  // USE_BROWSER_SPELLCHECKER
+
+#if BUILDFLAG(HAS_SPELLCHECK_PANEL)
+// Tells the browser to display or not display the SpellingPanel
+IPC_MESSAGE_ROUTED1(SpellCheckHostMsg_ShowSpellingPanel,
+                    bool /* if true, then show it, otherwise hide it*/)
+
+// Tells the browser to update the spelling panel with the given word.
+IPC_MESSAGE_ROUTED1(SpellCheckHostMsg_UpdateSpellingPanelWithMisspelledWord,
+                    base::string16 /* the word to update the panel with */)
+#endif