Clean up a few includes, introduce iwyu.

src/ports/SkFontMgr_fontconfig.cpp

 /*
  * Copyright 2014 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #include "SkDataTable.h"
+#include "SkFixed.h"
 #include "SkFontDescriptor.h"
 #include "SkFontHost_FreeType_common.h"
 #include "SkFontMgr.h"
 #include "SkFontStyle.h"
 #include "SkMath.h"
 #include "SkMutex.h"
+#include "SkOSFile.h"
+#include "SkRefCnt.h"
+#include "SkStream.h"
 #include "SkString.h"
-#include "SkStream.h"
 #include "SkTDArray.h"
+#include "SkTemplates.h"
+#include "SkTypeface.h"
 #include "SkTypefaceCache.h"
-#include "SkOSFile.h"
+#include "SkTypes.h"
 
 #include <fontconfig/fontconfig.h>
+#include <string.h>
+
+class SkData;
 
 // FC_POSTSCRIPT_NAME was added with b561ff20 which ended up in 2.10.92
 // Ubuntu 12.04 is on 2.8.0, 13.10 is on 2.10.93
 // Debian 7 is on 2.9.0, 8 is on 2.11
 // OpenSUSE 12.2 is on 2.9.0, 12.3 is on 2.10.2, 13.1 2.11.0
 // Fedora 19 is on 2.10.93
 #ifndef FC_POSTSCRIPT_NAME
 #    define FC_POSTSCRIPT_NAME  "postscriptname"
 #endif
 
@@ skipping 833 matching lines @@
             return typeface.detach();
         }
 
         return this->matchFamilyStyle(NULL, style);
     }
 };
 
 SK_API SkFontMgr* SkFontMgr_New_FontConfig(FcConfig* fc) {
     return new SkFontMgr_fontconfig(fc);
 }