Fix some latin-1 webkit units tests

src/runtime.cc

Index: src/runtime.cc
diff --git a/src/runtime.cc b/src/runtime.cc
index 6346e5b59600dd24b5e3da5d262db462cc0774c0..81bac94330d62f7c9b765984231b69cdf8e29413 100644
--- a/src/runtime.cc
+++ b/src/runtime.cc
@@ -5048,8 +5048,8 @@ RUNTIME_FUNCTION(MaybeObject*, Runtime_StringToNumber) {
       // Fast check for a junk value. A valid string may start from a
       // whitespace, a sign ('+' or '-'), the decimal point, a decimal digit or
       // the 'I' character ('Infinity'). All of that have codes not greater than
-      // '9' except 'I'.
-      if (data[start_pos] != 'I') {
+      // '9' except 'I' and  .
+      if (data[start_pos] != 'I' && data[start_pos] != 0xa0) {
         return isolate->heap()->nan_value();
       }
     } else if (len - start_pos < 10 && AreDigits(data, start_pos, len)) {