Revert of Suppress an uninitialized value in...

Revert of Suppress an uninitialized value in KeyboardLayoutManager::SetChildBounds. (patchset #1 of https://codereview.chromium.org/502183003/)

Reason for revert:
https://codereview.chromium.org/480723006/ fixed this.

Original issue's description:
> Suppress an uninitialized value in KeyboardLayoutManager::SetChildBounds.
>
> BUG=407467
> TBR=bshe@chromium.org
>
> Committed: https://chromium.googlesource.com/chromium/src/+/1598e5ab15e3c24f6d17e2214e61185d1098c915

TBR=bshe@chromium.org
NOTREECHECKS=true
NOTRY=true
BUG=407467

Review URL: https://codereview.chromium.org/506953002

Cr-Commit-Position: refs/heads/master@{#291907}

tools/valgrind/memcheck/suppressions.txt

@@ -6283,9 +6283,3 @@
    fun:_ZN5blink11RenderBlock13paintContentsERNS_9PaintInfoERKNS_11LayoutPointE
    fun:_ZN5blink11RenderBlock11paintObjectERNS_9PaintInfoERKNS_11LayoutPointE
 }
-{
-   bug_407467
-   Memcheck:Uninitialized
-   fun:_ZN8keyboard21KeyboardLayoutManager14SetChildBounds*
-   fun:_ZN4aura6Window9SetBounds*
-}