WebFonts cache-aware timeout adaptation

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 e6f9a8c7845dd7d7ec5e0fb09577a04afb6d853a..1b05405e3f390a21168366a79137fc7c7bd58201 100644
--- a/third_party/WebKit/Source/core/css/RemoteFontFaceSource.cpp
+++ b/third_party/WebKit/Source/core/css/RemoteFontFaceSource.cpp
@@ -9,6 +9,7 @@
 #include "core/css/CSSFontSelector.h"
 #include "core/dom/Document.h"
 #include "core/fetch/ResourceFetcher.h"
+#include "core/fetch/ResourceLoader.h"
 #include "core/inspector/ConsoleMessage.h"
 #include "core/loader/FrameLoaderClient.h"
 #include "core/page/NetworkStateNotifier.h"
@@ -56,7 +57,7 @@ RemoteFontFaceSource::RemoteFontFaceSource(FontResource* font,
     : m_font(font),
       m_fontSelector(fontSelector),
       m_display(display),
-      m_period(display == FontDisplaySwap ? SwapPeriod : BlockPeriod),
+      m_period(BlockPeriod),
       m_histograms(font->url().protocolIsData()
                        ? FontLoadHistograms::FromDataURL
                        : font->isLoaded() ? FontLoadHistograms::FromMemoryCache
@@ -64,7 +65,6 @@ RemoteFontFaceSource::RemoteFontFaceSource(FontResource* font,
                    m_display),
       m_isInterventionTriggered(false) {
   ThreadState::current()->registerPreFinalizer(this);
-  m_font->addClient(this);
 
   if (shouldTriggerWebFontsIntervention()) {
     m_isInterventionTriggered = true;
@@ -74,6 +74,13 @@ RemoteFontFaceSource::RemoteFontFaceSource(FontResource* font,
         "Slow network is detected. Fallback font will be used while loading: " +
             m_font->url().elidedString()));
   }
+
+  if (m_display == FontDisplaySwap && !shouldTriggerCacheAwareAdaptation())
+    m_period = SwapPeriod;
+
+  // Font loading callbacks may be called in addClient(), make sure |m_period|
+  // is properly set before calling.
+  m_font->addClient(this);
 }
 
 RemoteFontFaceSource::~RemoteFontFaceSource() {}
@@ -161,8 +168,14 @@ void RemoteFontFaceSource::fontLoadLongLimitExceeded(FontResource*) {
   m_histograms.longLimitExceeded(m_isInterventionTriggered);
 }
 
+void RemoteFontFaceSource::willReloadAfterDiskCacheMiss(const FontResource*) {
+  DCHECK(m_font->isLoading());
+  if (m_display == FontDisplaySwap)
+    switchToSwapPeriod();
+}
+
 void RemoteFontFaceSource::switchToSwapPeriod() {
-  ASSERT(m_period == BlockPeriod);
+  DCHECK_EQ(m_period, BlockPeriod);
   m_period = SwapPeriod;
 
   pruneTable();
@@ -177,7 +190,7 @@ void RemoteFontFaceSource::switchToSwapPeriod() {
 void RemoteFontFaceSource::switchToFailurePeriod() {
   if (m_period == BlockPeriod)
     switchToSwapPeriod();
-  ASSERT(m_period == SwapPeriod);
+  DCHECK_EQ(m_period, SwapPeriod);
   m_period = FailurePeriod;
 }
 
@@ -200,6 +213,16 @@ bool RemoteFontFaceSource::shouldTriggerWebFontsIntervention() {
   return networkIsSlow && m_display == FontDisplayAuto;
 }
 
+bool RemoteFontFaceSource::shouldTriggerCacheAwareAdaptation() {
+  if (m_font->stillNeedsLoad() &&
+      m_font->options().cacheAwareLoadingEnabled == IsCacheAwareLoadingEnabled)
+    return true;
+  if (m_font->isLoading() && m_font->loader()->isCacheAwareLoadingActivated())
+    return true;
+  // willReloadAfterDiskCacheMiss() will not be called.
+  return false;
+}
+
 PassRefPtr<SimpleFontData> RemoteFontFaceSource::createFontData(
     const FontDescription& fontDescription) {
   if (!isLoaded())