[WIP] WebFonts cache-aware timeout adaption

third_party/WebKit/Source/core/css/RemoteFontFaceSource.cpp

Index: third_party/WebKit/Source/core/css/RemoteFontFaceSource.cpp
diff --git a/third_party/WebKit/Source/core/css/RemoteFontFaceSource.cpp b/third_party/WebKit/Source/core/css/RemoteFontFaceSource.cpp
index 57e48b357383b9e79a6dbd8d8a53cf995dde2af5..e058a71841c01b64337d670f2f3bb9f15cfb04c3 100644
--- a/third_party/WebKit/Source/core/css/RemoteFontFaceSource.cpp
+++ b/third_party/WebKit/Source/core/css/RemoteFontFaceSource.cpp
@@ -154,23 +154,30 @@ void RemoteFontFaceSource::fontLoadLongLimitExceeded(FontResource*) {
   m_histograms.longLimitExceeded(m_isInterventionTriggered);
 }
 
-void RemoteFontFaceSource::switchToSwapPeriod() {
-  ASSERT(m_period == BlockPeriod);
-  m_period = SwapPeriod;
+void RemoteFontFaceSource::willReloadAfterDiskCacheMiss(const FontResource*) {
+  if (m_period == SwapPeriod || m_period == FailurePeriod)
+    didBecomeVisibleFallback();

[Kunihiko Sakamoto, 2016/10/11 08:07:38]

We should move to next period here, instead of keeping it and complicating the
condition for visibility of fallback font.

[Shao-Chuan Lee, 2016/10/11 10:58:48]

Done.

+}
 
+void RemoteFontFaceSource::didBecomeVisibleFallback() {
   pruneTable();
   if (m_face) {
     m_fontSelector->fontFaceInvalidated();
     m_face->didBecomeVisibleFallback(this);
   }
+}
 
+void RemoteFontFaceSource::switchToSwapPeriod() {
+  DCHECK(m_period == BlockPeriod);
+  m_period = SwapPeriod;
+  didBecomeVisibleFallback();
   m_histograms.recordFallbackTime(m_font.get());
 }
 
 void RemoteFontFaceSource::switchToFailurePeriod() {
   if (m_period == BlockPeriod)
     switchToSwapPeriod();
-  ASSERT(m_period == SwapPeriod);
+  DCHECK(m_period == SwapPeriod);
   m_period = FailurePeriod;
 }
 
@@ -193,6 +200,25 @@ bool RemoteFontFaceSource::shouldTriggerWebFontsIntervention() {
   return networkIsSlow && m_display == FontDisplayAuto;
 }
 
+bool RemoteFontFaceSource::shouldUseInvisibleFallback() const {
+  if (m_period == BlockPeriod)
+    return true;
+  if (m_font->resourceRequest().isCacheAwareLoadingActivated()) {
+    switch (m_display) {
+      case FontDisplaySwap:
+      case FontDisplayFallback:
+      case FontDisplayOptional:
+        return true;
+      case FontDisplayAuto:
+      case FontDisplayBlock:
+        break;
+      case FontDisplayEnumMax:
+        NOTREACHED();
+    }
+  }
+  return false;
+}
+
 PassRefPtr<SimpleFontData> RemoteFontFaceSource::createFontData(
     const FontDescription& fontDescription) {
   if (!isLoaded())
@@ -223,8 +249,8 @@ PassRefPtr<SimpleFontData> RemoteFontFaceSource::createLoadingFallbackFontData(
     return nullptr;
   }
   RefPtr<CSSCustomFontData> cssFontData = CSSCustomFontData::create(
-      this, m_period == BlockPeriod ? CSSCustomFontData::InvisibleFallback
-                                    : CSSCustomFontData::VisibleFallback);
+      this, shouldUseInvisibleFallback() ? CSSCustomFontData::InvisibleFallback
+                                         : CSSCustomFontData::VisibleFallback);
   return SimpleFontData::create(temporaryFont->platformData(), cssFontData);
 }