More valgrind suppressions

tools/valgrind/memcheck/suppressions.txt

 # There are three kinds of suppressions in this file.
 # 1. third party stuff we have no control over
 #
 # 2. intentional unit test errors, or stuff that is somehow a false positive
 # in our own code, or stuff that is so trivial it's not worth fixing
 #
 # 3. Suppressions for real chromium bugs that are not yet fixed.
 # These should all be in chromium's bug tracking system (but a few aren't yet).
 # Periodically we should sweep this file and the bug tracker clean by
 # running overnight and removing outdated bugs/suppressions.
@@ skipping 1110 matching lines @@
    bug_20778
    Memcheck:Cond
    fun:_ZN7WebCore10XSSAuditor23CachingURLCanonicalizer15canonicalizeURLERKNS_6StringERKNS_12TextEncodingEb
 }
 {
    bug_20805
    Memcheck:Leak
    fun:_Znw*
    fun:_ZN7history14HistoryBackend12AddPageVisitERK4GURLN4base4TimeExj
 }
+{
+   bug_20939
+   Memcheck:Cond
+   fun:_ZN7WebCore9CSSParser9validUnitEPNS_14CSSParserValueENS0_5UnitsEb
+   fun:_ZN7WebCore9CSSParser10parseValueEib
+   fun:_Z10cssyyparsePv
+}
+{
+   bug_20941
+   Memcheck:Cond
+   fun:_ZNK7WebCore23RenderThemeChromiumSkia21adjustSliderThumbSizeEPNS_12RenderObjectE
+   fun:_ZN7WebCore12RenderSlider6layoutEv
+   ...
+   fun:_ZN7WebCore10RenderView6layoutEv
+   fun:_ZN7WebCore9FrameView6layoutEb
+   fun:_ZN7WebCore8Document12updateLayoutEv
+}