Clang: the tip-of-tree version is now 8.0.0svn

It was bumped in LLVM r338537.

R=thakis,rnk

Bug: 869850
Change-Id: Ida95943088bdf8921b5974e7e80a80e2739db01b
Reviewed-on: https://chromium-review.googlesource.com/1158580Reviewed-by: Nico Weber <thakis@chromium.org>
Commit-Queue: Hans Wennborg <hans@chromium.org>
Cr-Commit-Position: refs/heads/master@{#579800}

build/toolchain/toolchain.gni

@@ -48,7 +48,12 @@ hermetic_xcode_path =
 declare_args() {
   if (is_clang) {
     # Clang compiler version. Clang files are placed at version-dependent paths.
-    clang_version = "7.0.0"
+    if (llvm_force_head_revision) {
+      clang_version = "8.0.0"
+    } else {
+      # TODO(hans): Trunk version was updated; remove after the next roll.
+      clang_version = "7.0.0"
+    }
   }
 }
 

tools/clang/scripts/update.py

@@ -903,6 +903,11 @@ def main():
       args.force_local_build):
     AddSvnToPathOnWin()
 
+  if use_head_revision:
+    # TODO(hans): Trunk version was updated; remove after the next roll.
+    global VERSION
+    VERSION = '8.0.0'
+
   if args.verify_version and args.verify_version != VERSION:
     print 'VERSION is %s but --verify-version argument was %s, exiting.' % (
         VERSION, args.verify_version)