icu: Warning tweaks in preparation for the next clang roll.

icu.gyp

Index: icu.gyp
===================================================================
--- icu.gyp	(revision 122103)
+++ icu.gyp	(working copy)
@@ -333,6 +333,12 @@
                   # the header should use U_NAMESPACE_BEGIN instead.
                   # http://bugs.icu-project.org/trac/ticket/9054
                   '-Wno-header-hygiene',
+                  # ICU does some tricky array allocation that trips over
+                  # -Warray-bounds. It seems to be harmless, see
+                  # http://crbug.com/84851.
+                  '-Wno-array-bounds',
+                  # Looks like a real issue, see http://crbug.com/114660
+                  '-Wno-return-type-c-linkage',
                 ],
               },
               'cflags': [
@@ -340,6 +346,8 @@
                 '-Wno-logical-op-parentheses',
                 '-Wno-tautological-compare',
                 '-Wno-header-hygiene',
+                '-Wno-array-bounds',
+                '-Wno-return-type-c-linkage',
               ],
             }],
           ],