This change consolidates the code to generate type signature modifiers into `Signatures.TypeSignature`.
Although this mostly consists of moving the code from `ClassWriterImpl` and `Utils` to `Signatures`, I also avoided the need to split the modifiers string when processing preview modifiers by returning a `List<String>` instead of a `String` in what used to be `Utils.modifiersToString` and is now `TypeSignature.getModifiers`. ------------- Commit messages: - JDK-8266748: Make getModifiers() non-static - JDK-8266748: Move modifiers code to Signatures.java Changes: https://git.openjdk.java.net/jdk/pull/4142/files Webrev: https://webrevs.openjdk.java.net/?repo=jdk&pr=4142&range=00 Issue: https://bugs.openjdk.java.net/browse/JDK-8266748 Stats: 261 lines in 5 files changed: 118 ins; 123 del; 20 mod Patch: https://git.openjdk.java.net/jdk/pull/4142.diff Fetch: git fetch https://git.openjdk.java.net/jdk pull/4142/head:pull/4142 PR: https://git.openjdk.java.net/jdk/pull/4142
