Add RenderTextLinux Heapcheck and Valgrind suppressions.

tools/valgrind/memcheck/suppressions.txt

 # There are four 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 # running overnight and removing outdated bugs/suppressions.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 6554 matching lines @@
    fun:_ZN7WebCore18RenderLayerBacking13updateFiltersEPKNS_11RenderStyleE
    fun:_ZN7WebCore18RenderLayerBacking*GraphicsLayer*
 }
 {
    bug_173356
    Memcheck:Overlap
    fun:memcpy
    fun:_ZN3gpu5gles2*Immediate4InitE*
    fun:_ZN3gpu5gles2*GLES2ImplementationTest_*_Test8TestBodyEv
 }
+{
+bug_173597_a

[Timur Iskhodzhanov, 2013/02/01 10:11:47]

nit: indents

+Memcheck:Leak
+fun:malloc
+fun:g_malloc
+fun:g_slice_alloc
+fun:pango_attr_list_get_iterator
+fun:_ZN3gfx35RenderTextTest_PangoAttributes_Test8TestBodyEv
+}
+{
+bug_173597_b
+Memcheck:Leak
+fun:realloc
+fun:g_realloc
+fun:g_string_maybe_expand
+fun:g_string_insert_len
+fun:pango_font_description_to_string
+fun:_ZN3gfx35RenderTextTest_PangoAttributes_Test8TestBodyEv
+}