Align srcset parsing with spec changes

Source/core/html/parser/HTMLSrcsetParserTest.cpp

Index: Source/core/html/parser/HTMLSrcsetParserTest.cpp
diff --git a/Source/core/html/parser/HTMLSrcsetParserTest.cpp b/Source/core/html/parser/HTMLSrcsetParserTest.cpp
index 2ab349e925dc0b23c90e06f2579539d14551d390..418e19ebb0d3d5a9605be9042c3ee209fe580eb1 100644
--- a/Source/core/html/parser/HTMLSrcsetParserTest.cpp
+++ b/Source/core/html/parser/HTMLSrcsetParserTest.cpp
@@ -46,6 +46,12 @@ TEST(HTMLSrcsetParserTest, Basic)
         {5.0, -1, "", "1x,,  ,   x    ,2x  , 1x.gif, 3x, 4x.gif 4x 100h, 5x.gif 5, dx.gif dx, 2x.gif   2x ,", "4x.gif", 4.0, -1},
         {1.0, 400, "", "400.gif 400w, 6000.gif 6000w", "400.gif", 1.0, 400},
         {2.0, 400, "", "400.gif 400w, 6000.gif 6000w", "6000.gif", 15.0, 6000},
+        {1.0, 400, "src.gif", "800.gif 800w", "800.gif", 2.0, 800},
+        {1.0, 400, "src.gif", "0.gif 0w, 800.gif 800w", "800.gif", 2.0, 800},
+        {1.0, 400, "src.gif", "0.gif 0w, 2x.gif 2x", "src.gif", 1.0, -1},
+        {1.0, 400, "src.gif", "800.gif 2x, 1600.gif 1600w", "800.gif", 2.0, -1},
+        {1.0, 400, "", "400.gif 400w, 2x.gif 2x", "400.gif", 1.0, 400},
+        {2.0, 400, "", "400.gif 400w, 2x.gif 2x", "2x.gif", 2.0, -1},
         {1.0, 0, "", "400.gif 400w, 6000.gif 6000w", "400.gif", std::numeric_limits<float>::infinity(), 400},
         {0, 0, 0, 0, 0, 0} // Do not remove the terminator line.
     };