[test] Mark slow msan tests

TBR=mstarzinger@chromium.org,rmcilroy@chromium.org
NOTRY=true

Change-Id: I355953b0b24a64e3c5e1a43cdeaa8ec2650b0988
Reviewed-on: https://chromium-review.googlesource.com/453459Reviewed-by: Michael Achenbach <machenbach@chromium.org>
Commit-Queue: Michael Achenbach <machenbach@chromium.org>
Cr-Commit-Position: refs/heads/master@{#43737}

test/mjsunit/mjsunit.status

@@ -369,6 +369,11 @@
 
   # Flaky with baseline?
   'regress/regress-2185-2': [SKIP],
+
+  # Slow tests with --nocrankshaft.
+  'compiler/osr-one': [PASS, SLOW],
+  'compiler/osr-two': [PASS, SLOW],
+  'wasm/grow-memory': [PASS, SLOW],
 }],  # 'msan == True'
 
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