Update jdt.core to I20150428-0800 (M7 warm-up).
Manually merge from origin (bogus lineend changes):
- NullTypeAnnotationTest
- AstConverter18Test (no real change)
- FormatterBugsTests (no real change)
- SpacePreparator
- SourceTypeBinding

diff --git a/org.eclipse.jdt.core/plugin.properties b/org.eclipse.jdt.core/plugin.properties
index 8f99944..1f11bc3 100644
--- a/org.eclipse.jdt.core/plugin.properties
+++ b/org.eclipse.jdt.core/plugin.properties
@@ -30,3 +30,4 @@
 jarManifestName=JAR Manifest File
 traceComponentLabel=JDT Core
 javaFormatterName=Java Formatter
+defaultJavaFormatterName=Eclipse [built-in]