Make SkFontMgr interface const.

src/ports/SkFontHost_linux.cpp

Index: src/ports/SkFontHost_linux.cpp
diff --git a/src/ports/SkFontHost_linux.cpp b/src/ports/SkFontHost_linux.cpp
index 9eabac31c6a06c3beb4de898905abcd6bf11abe9..2f962d7d40d35e1cc6854eb2c065859e69a9eaff 100644
--- a/src/ports/SkFontHost_linux.cpp
+++ b/src/ports/SkFontHost_linux.cpp
@@ -215,21 +215,21 @@ public:
     }
 
 protected:
-    virtual int onCountFamilies() SK_OVERRIDE {
+    virtual int onCountFamilies() const SK_OVERRIDE {
         return fFamilies.count();
     }
 
-    virtual void onGetFamilyName(int index, SkString* familyName) SK_OVERRIDE {
+    virtual void onGetFamilyName(int index, SkString* familyName) const SK_OVERRIDE {
         SkASSERT(index < fFamilies.count());
         familyName->set(fFamilies[index]->fFamilyName);
     }
 
-    virtual SkFontStyleSet_Custom* onCreateStyleSet(int index) SK_OVERRIDE {
+    virtual SkFontStyleSet_Custom* onCreateStyleSet(int index) const SK_OVERRIDE {
         SkASSERT(index < fFamilies.count());
         return SkRef(fFamilies[index].get());
     }
 
-    virtual SkFontStyleSet_Custom* onMatchFamily(const char familyName[]) SK_OVERRIDE {
+    virtual SkFontStyleSet_Custom* onMatchFamily(const char familyName[]) const SK_OVERRIDE {
         for (int i = 0; i < fFamilies.count(); ++i) {
             if (fFamilies[i]->fFamilyName.equals(familyName)) {
                 return SkRef(fFamilies[i].get());
@@ -239,14 +239,14 @@ protected:
     }
 
     virtual SkTypeface* onMatchFamilyStyle(const char familyName[],
-                                           const SkFontStyle& fontStyle) SK_OVERRIDE
+                                           const SkFontStyle& fontStyle) const SK_OVERRIDE
     {
         SkAutoTUnref<SkFontStyleSet> sset(this->matchFamily(familyName));
         return sset->matchStyle(fontStyle);
     }
 
     virtual SkTypeface* onMatchFaceStyle(const SkTypeface* familyMember,
-                                         const SkFontStyle& fontStyle) SK_OVERRIDE
+                                         const SkFontStyle& fontStyle) const SK_OVERRIDE
     {
         for (int i = 0; i < fFamilies.count(); ++i) {
             for (int j = 0; j < fFamilies[i]->fStyles.count(); ++j) {
@@ -258,12 +258,12 @@ protected:
         return NULL;
     }
 
-    virtual SkTypeface* onCreateFromData(SkData* data, int ttcIndex) SK_OVERRIDE {
+    virtual SkTypeface* onCreateFromData(SkData* data, int ttcIndex) const SK_OVERRIDE {
         SkAutoTUnref<SkStream> stream(new SkMemoryStream(data));
         return this->createFromStream(stream, ttcIndex);
     }
 
-    virtual SkTypeface* onCreateFromStream(SkStream* stream, int ttcIndex) SK_OVERRIDE {
+    virtual SkTypeface* onCreateFromStream(SkStream* stream, int ttcIndex) const SK_OVERRIDE {
         if (NULL == stream || stream->getLength() <= 0) {
             SkDELETE(stream);
             return NULL;
@@ -279,13 +279,13 @@ protected:
         }
     }
 
-    virtual SkTypeface* onCreateFromFile(const char path[], int ttcIndex) SK_OVERRIDE {
+    virtual SkTypeface* onCreateFromFile(const char path[], int ttcIndex) const SK_OVERRIDE {
         SkAutoTUnref<SkStream> stream(SkStream::NewFromFile(path));
         return stream.get() ? this->createFromStream(stream, ttcIndex) : NULL;
     }
 
     virtual SkTypeface* onLegacyCreateTypeface(const char familyName[],
-                                               unsigned styleBits) SK_OVERRIDE
+                                               unsigned styleBits) const SK_OVERRIDE
     {
         SkTypeface::Style oldStyle = (SkTypeface::Style)styleBits;
         SkFontStyle style = SkFontStyle(oldStyle & SkTypeface::kBold