RFR: Merge lworld [v2]

[Vicente Romero]

> Merge branch 'lworld' into lw5_merge_lworld
> # Conflicts:
> #	src/java.base/share/classes/java/lang/invoke/ConstantBootstraps.java
> #	src/java.compiler/share/classes/javax/lang/model/element/Modifier.java
> #	src/jdk.compiler/share/classes/com/sun/tools/javac/code/Types.java
> #	src/jdk.compiler/share/classes/com/sun/tools/javac/comp/Attr.java
> #	src/jdk.compiler/share/classes/com/sun/tools/javac/comp/Lower.java
> #	src/jdk.compiler/share/classes/com/sun/tools/javac/comp/TransTypes.java
> #	src/jdk.compiler/share/classes/com/sun/tools/javac/jvm/ClassReader.java
> #	src/jdk.compiler/share/classes/com/sun/tools/javac/parser/JavacParser.java
> #	test/langtools/tools/javac/diags/examples.not-yet.txt

Vicente Romero has updated the pull request with a new target base due to a merge or a rebase. The pull request now contains 60 commits:

 - Merge branch 'lworld' into lw5_merge_lworld
   
   # Conflicts:
   #	src/java.base/share/classes/java/lang/invoke/ConstantBootstraps.java
   #	src/java.compiler/share/classes/javax/lang/model/element/Modifier.java
   #	src/jdk.compiler/share/classes/com/sun/tools/javac/code/Types.java
   #	src/jdk.compiler/share/classes/com/sun/tools/javac/comp/Attr.java
   #	src/jdk.compiler/share/classes/com/sun/tools/javac/comp/Lower.java
   #	src/jdk.compiler/share/classes/com/sun/tools/javac/comp/TransTypes.java
   #	src/jdk.compiler/share/classes/com/sun/tools/javac/jvm/ClassReader.java
   #	src/jdk.compiler/share/classes/com/sun/tools/javac/parser/JavacParser.java
   #	test/langtools/tools/javac/diags/examples.not-yet.txt
 - 8340125: [lw5] null checks are not being generated for method invocations and array writes
 - Merge lworld
 - 8340027: [lw5] the ACC_STRICT flag is not being set for non-nullable static fields
 - Merge lworld
 - 8339357: [lw5] make non-nullable instance fields strict
 - 8339339: [lw5] javac should issue an error if a null-restricted field is left uninitialized, fix override related warnings
 - 8338910: [lw5] enhance the Signature attribute to represent nullability
 - Improve support for nullable types and arrays
 - 8339087: [lw5] remove parametric types related warnings
 - ... and 50 more: https://git.openjdk.org/valhalla/compare/115d3dea...4a7d52c6

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

Changes: https://git.openjdk.org/valhalla/pull/1295/files
  Webrev: https://webrevs.openjdk.org/?repo=valhalla&pr=1295&range=01
  Stats: 6859 lines in 106 files changed: 6738 ins; 5 del; 116 mod
  Patch: https://git.openjdk.org/valhalla/pull/1295.diff
  Fetch: git fetch https://git.openjdk.org/valhalla.git pull/1295/head:pull/1295

PR: https://git.openjdk.org/valhalla/pull/1295