Roll DEPS for clang to 63ca7c81.

DEPS

Index: DEPS
diff --git a/DEPS b/DEPS
index 87511c7d64401fc4fb1f22fee4064e26b6c7a6ce..68583005ef7e2a39149bf4d899003b11a8af74f6 100644
--- a/DEPS
+++ b/DEPS
@@ -4,11 +4,11 @@ vars = {
   'chromium_git': 'https://chromium.googlesource.com',
   'pdfium_git': 'https://pdfium.googlesource.com',
 
-  'android_ndk_revision': '5022f40f12953c02b2614c5f7beb981ec5d0e833',
-  'build_revision': 'b73bafdd0ff0efc8835de6e646b47eec0a2a38a4',
+  'android_ndk_revision': '26d93ec07f3ce2ec2cdfeae1b21ee6f12ff868d8',
+  'build_revision': '98f2d80a58aa2ba234f1d37e6844aea81554a903',
   'buildtools_revision': '5fd66957f08bb752dca714a591c84587c9d70762',
   'catapult_revision': '327256cb1c387e62a2c7e6960e2398867665fb51',
-  'clang_revision': '797371be0a75c9892d6acb486d0430915ea538a6',
+  'clang_revision': '63ca7c8159abd3f5375ffaba72b04eb91feca3bb',
   'cygwin_revision': 'c89e446b273697fadf3a10ff1007a97c0b7de6df',
   'gen_library_loader_revision': '916d4acd8b2cde67a390737dfba90b3c37de23a1',
   'gmock_revision': '29763965ab52f24565299976b936d1265cb6a271',