FontLoadHistograms: move maySetDataSource() impl out of header

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

Index: third_party/WebKit/Source/core/css/RemoteFontFaceSource.h
diff --git a/third_party/WebKit/Source/core/css/RemoteFontFaceSource.h b/third_party/WebKit/Source/core/css/RemoteFontFaceSource.h
index 36e203efd2b241c930717cb54ee01ea0ceb20456..44a1385a2e055f1a99efb8ca0f9073ba5cd817cc 100644
--- a/third_party/WebKit/Source/core/css/RemoteFontFaceSource.h
+++ b/third_party/WebKit/Source/core/css/RemoteFontFaceSource.h
@@ -74,10 +74,7 @@ private:
         void recordRemoteFont(const FontResource*);
         bool hadBlankText() { return m_blankPaintTime; }
         DataSource dataSource() { return m_dataSource; }
-        // Classify as memory cache hit if |m_loadStartTime| is not set, i.e.
-        // this RemoteFontFaceSource instance didn't trigger FontResource
-        // loading.
-        void maySetDataSource(DataSource dataSource) { m_dataSource = (m_dataSource != FromUnknown) ? m_dataSource : (m_loadStartTime == 0) ? FromMemoryCache : dataSource; }
+        void maySetDataSource(DataSource);
     private:
         void recordLoadTimeHistogram(const FontResource*, int duration);
         void recordInterventionResult(bool isTriggered);