Always use user preference font before system fallback

third_party/WebKit/Source/platform/fonts/FontFallbackList.cpp

Index: third_party/WebKit/Source/platform/fonts/FontFallbackList.cpp
diff --git a/third_party/WebKit/Source/platform/fonts/FontFallbackList.cpp b/third_party/WebKit/Source/platform/fonts/FontFallbackList.cpp
index 6067f5b89fb397adf686d90ef33ae309a3a057a8..33c3f549bd77ffe4873ba3cc42ee387db45ee6ff 100644
--- a/third_party/WebKit/Source/platform/fonts/FontFallbackList.cpp
+++ b/third_party/WebKit/Source/platform/fonts/FontFallbackList.cpp
@@ -48,6 +48,7 @@ FontFallbackList::FontFallbackList()
     , m_familyIndex(0)
     , m_generation(FontCache::fontCache()->generation())
     , m_hasLoadingFallback(false)
+    , m_hasNonBlankFontData(false)
 {
 }
 
@@ -60,6 +61,7 @@ void FontFallbackList::invalidate(PassRefPtrWillBeRawPtr<FontSelector> fontSelec
     m_cachedPrimarySimpleFontData = 0;
     m_familyIndex = 0;
     m_hasLoadingFallback = false;
+    m_hasNonBlankFontData = false;
     if (m_fontSelector != fontSelector)
         m_fontSelector = fontSelector;
     m_fontSelectorVersion = m_fontSelector ? m_fontSelector->version() : 0;
@@ -155,33 +157,30 @@ const SimpleFontData* FontFallbackList::determinePrimarySimpleFontData(const Fon
 
 PassRefPtr<FontData> FontFallbackList::getFontData(const FontDescription& fontDescription, int& familyIndex) const
 {
-    RefPtr<FontData> result;
-
-    int startIndex = familyIndex;
-    const FontFamily* startFamily = &fontDescription.family();
-    for (int i = 0; startFamily && i < startIndex; i++)
-        startFamily = startFamily->next();
-    const FontFamily* currFamily = startFamily;
-    while (currFamily && !result) {
+    const FontFamily* currFamily = &fontDescription.family();
+    for (int i = 0; currFamily && i < familyIndex; i++)
+        currFamily = currFamily->next();
+
+    for (; currFamily; currFamily = currFamily->next()) {
         familyIndex++;
         if (currFamily->family().length()) {
+            RefPtr<FontData> result;
             if (m_fontSelector)
                 result = m_fontSelector->getFontData(fontDescription, currFamily->family());
-
             if (!result)
                 result = FontCache::fontCache()->getFontData(fontDescription, currFamily->family());
+            if (result)
+                return result.release();
         }
-        currFamily = currFamily->next();
     }
+    familyIndex = cAllFamiliesScanned;
 
-    if (!currFamily)
-        familyIndex = cAllFamiliesScanned;
-
-    if (result || startIndex)
-        return result.release();
+    if (m_hasNonBlankFontData)
+        return nullptr;
 
-    // If it's the primary font that we couldn't find, we try the following. In all other cases, we will
-    // just use per-character system fallback.
+    // If we couldn't find any non-blank font data in the family list, we try
+    // the following. In all other cases, we will just use per-character system
+    // fallback.
 
     if (m_fontSelector) {
         // Try the user's preferred standard font.
@@ -238,6 +237,8 @@ const FontData* FontFallbackList::fontDataAt(const FontDescription& fontDescript
         m_fontList.append(result);
         if (result->isLoadingFallback())
             m_hasLoadingFallback = true;
+        else

[drott, 2015/12/01 09:36:22]

Is there a way we could avoid the additional flag? Could it be expressed through
a combination of familyIndex and m_hasLoadingfallback? It seems a bit odd to me
that the flag is set outside of getFontData based on getFontData's result, and
then used inside the getFontData function.

+            m_hasNonBlankFontData = true;
     }
     return result.get();
 }