RFR: Merge lworld

[Vicente Romero]

Merge lworld into universal-tvars

-------------

Commit messages:
 - Merge branch 'lworld' into universal-tvars_merge_lworld_03_15
 - 8282695: [lworld] assert(oopDesc::is_oop(obj)) in compiler/valhalla/inlinetypes/TestUnloadedInlineTypeArray.java
 - 8282512: Remove usages of __WithField in compiler tests
 - 8282107: Valhalla: javac does not correctly recognize value class factory <init>
 - 8282079: [lworld] Generate Preload attribute in lambdas and proxies if value classes are referenced
 - 8282292: [lworld] runtime/valhalla/inlinetypes/WithFieldAccessorTest.java Xcomp C1 asserts
 - 8281283: Remove usages of __WithField in runtime tests
 - 8281323: [lworld] Unnecessary entries in Preload attribute
 - 8282108: [lworld] Enhance CreateSymbols to read Preload attribute

The webrevs contain the adjustments done while merging with regards to each parent branch:
 - universal-tvars: https://webrevs.openjdk.java.net/?repo=valhalla&pr=670&range=00.0
 - lworld: https://webrevs.openjdk.java.net/?repo=valhalla&pr=670&range=00.1

Changes: https://git.openjdk.java.net/valhalla/pull/670/files
  Stats: 3248 lines in 63 files changed: 1670 ins; 1331 del; 247 mod
  Patch: https://git.openjdk.java.net/valhalla/pull/670.diff
  Fetch: git fetch https://git.openjdk.java.net/valhalla pull/670/head:pull/670

PR: https://git.openjdk.java.net/valhalla/pull/670