RFR: 8264151: ciMethod::ensure_method_data() should return false is loading resulted in empty state

[Igor Veresov]

ciMethodData::load_data() can set the state of the MDO to empty (if it's replaying a compile). In this case we should return false from ensure_method_data().

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Commit messages:
 - ciMethod::ensure_method_data() should return false is loading resulted

Changes: https://git.openjdk.java.net/jdk/pull/3184/files
 Webrev: https://webrevs.openjdk.java.net/?repo=jdk&pr=3184&range=00
  Issue: https://bugs.openjdk.java.net/browse/JDK-8264151
  Stats: 3 lines in 1 file changed: 3 ins; 0 del; 0 mod
  Patch: https://git.openjdk.java.net/jdk/pull/3184.diff
  Fetch: git fetch https://git.openjdk.java.net/jdk pull/3184/head:pull/3184

PR: https://git.openjdk.java.net/jdk/pull/3184