Ignore optional whitespace after combinators when parsing CSS selectors.

For example, "div> .foo" was incorrectly parsed the same as "div>* .foo"
while it should be "div>.foo"

src/lxml/cssselect.py

@@ -693,6 +693,9 @@ def parse_selector(stream):
         elif peek in ('+', '>', '~'):
             # A combinator
             combinator = stream.next()
+            # Ignore optional whitespace after a combinator
+            while stream.peek() == ' ':
+                stream.next()
         else:
             combinator = ' '
         consumed = len(stream.used)

src/lxml/tests/test_css.txt

@@ -22,6 +22,10 @@ Then of parsing:
     Or([Element[div], Class[Element[td].foo], CombinedSelector[Class[Element[div].bar] <followed> Element[span]]])
     >>> parse('div > p')
     CombinedSelector[Element[div] > Element[p]]
+    >>> parse('div>.foo')
+    CombinedSelector[Element[div] > Class[Element[*].foo]]
+    >>> parse('div > .foo')
+    CombinedSelector[Element[div] > Class[Element[*].foo]]
     >>> parse('td:first')
     Pseudo[Element[td]:first]
     >>> parse('a[name]')

src/lxml/tests/test_css_select.txt

@@ -140,6 +140,8 @@ Now, the tests:
     li-div
     >>> pcss('div > div')
     empty
+    >>> pcss('div>.c', 'div > .c')
+    first-ol
     >>> pcss('div + div')
     foobar-div
     >>> pcss('a ~ a')