Paint buffered range closest to the current play position

Source/core/html/TimeRanges.cpp

Index: Source/core/html/TimeRanges.cpp
diff --git a/Source/core/html/TimeRanges.cpp b/Source/core/html/TimeRanges.cpp
index b41ff687be6ef94a79097aae11817ebe34a2e9c4..23d8cb1d533fa4a13046bf38c0950af82959a50b 100644
--- a/Source/core/html/TimeRanges.cpp
+++ b/Source/core/html/TimeRanges.cpp
@@ -211,6 +211,35 @@ double TimeRanges::nearest(double newPlaybackPosition, double currentPlaybackPos
     return bestMatch;
 }
 
+unsigned TimeRanges::nearestRange(double position) const
+{
+    unsigned count = length();
+    unsigned bestMatch = 0;
+    double bestDelta = std::numeric_limits<double>::infinity();
+    for (unsigned ndx = 0; ndx < count; ++ndx) {
+        double startTime = start(ndx, IGNORE_EXCEPTION);
+        double endTime = end(ndx, IGNORE_EXCEPTION);
+        if (position >= startTime && position <= endTime) {
+            return ndx;
+        }
+
+        double delta;
+        if (position < startTime) {
+            delta = startTime - position;
+        } else {
+            delta = position - endTime;
+        }
+
+        // Prioritize later ranges
+        if (delta <= bestDelta) {
+            bestDelta = delta;
+            bestMatch = ndx;
+        }
+    }
+
+    return bestMatch;
+}
+
 DEFINE_TRACE(TimeRanges)
 {
     visitor->trace(m_ranges);