Fixing typo in allocator_shim.h documentation.

Bug: None
Change-Id: I91c5141b86826badad4d61e26c2f0ef0acf37e35
No-Try: True
Reviewed-on: https://chromium-review.googlesource.com/1018105
Commit-Queue: Mirko Bonadei <mbonadei@chromium.org>
Reviewed-by: Will Harris <wfh@chromium.org>
Cr-Commit-Position: refs/heads/master@{#552079}

CrOS-Libchrome-Original-Commit: c347e40ed386bc63c01bb3bb8243084681c2056b
diff --git a/base/allocator/allocator_shim.h b/base/allocator/allocator_shim.h
index 65ac1eb..527e414 100644
--- a/base/allocator/allocator_shim.h
+++ b/base/allocator/allocator_shim.h
@@ -13,7 +13,7 @@
 namespace base {
 namespace allocator {
 
-// Allocator Shim API. Allows to to:
+// Allocator Shim API. Allows to:
 //  - Configure the behavior of the allocator (what to do on OOM failures).
 //  - Install new hooks (AllocatorDispatch) in the allocator chain.