Roll v8-crosswalk (9b0508c -> 50e7d31)

50e7d31 Fixed a limit for static initializers (cherry picked from commit c4235bbfec17fa203ecac0aec1c95901a2f7bf84)
35425e2 V8 profiling patch rebased on Chromium v34 (cherry picked from commit 4c47b893f2299aebbe796f22d15bb8c0182e8)