Encapsulate FontFallbackList's page access logic.

Source/platform/fonts/Font.cpp

Index: Source/platform/fonts/Font.cpp
diff --git a/Source/platform/fonts/Font.cpp b/Source/platform/fonts/Font.cpp
index a94a6ccef24bfb7006ea321c8457d97f7ab691f6..8b59819871361bcc28f973496d1ec129ed465926 100644
--- a/Source/platform/fonts/Font.cpp
+++ b/Source/platform/fonts/Font.cpp
@@ -414,13 +414,10 @@ std::pair<GlyphData, GlyphPage*> Font::glyphDataAndPageForCharacter(UChar32 c, b
 
     unsigned pageNumber = (c / GlyphPage::size);
 
-    GlyphPageTreeNode* node = pageNumber ? m_fontFallbackList->m_pages.get(pageNumber) : m_fontFallbackList->m_pageZero;
+    GlyphPageTreeNode* node = m_fontFallbackList->getPageNode(pageNumber);
     if (!node) {
         node = GlyphPageTreeNode::getRootChild(fontDataAt(0), pageNumber);
-        if (pageNumber)
-            m_fontFallbackList->m_pages.set(pageNumber, node);
-        else
-            m_fontFallbackList->m_pageZero = node;
+        m_fontFallbackList->setPageNode(pageNumber, node);
     }
 
     GlyphPage* page = 0;
@@ -454,10 +451,7 @@ std::pair<GlyphData, GlyphPage*> Font::glyphDataAndPageForCharacter(UChar32 c, b
 
             // Proceed with the fallback list.
             node = node->getChild(fontDataAt(node->level()), pageNumber);
-            if (pageNumber)
-                m_fontFallbackList->m_pages.set(pageNumber, node);
-            else
-                m_fontFallbackList->m_pageZero = node;
+            m_fontFallbackList->setPageNode(pageNumber, node);
         }
     }
     if (variant != NormalVariant) {
@@ -491,10 +485,7 @@ std::pair<GlyphData, GlyphPage*> Font::glyphDataAndPageForCharacter(UChar32 c, b
 
             // Proceed with the fallback list.
             node = node->getChild(fontDataAt(node->level()), pageNumber);
-            if (pageNumber)
-                m_fontFallbackList->m_pages.set(pageNumber, node);
-            else
-                m_fontFallbackList->m_pageZero = node;
+            m_fontFallbackList->setPageNode(pageNumber, node);
         }
     }