Handle extra semis in import lists

as a work-around for https://bugs.openjdk.java.net/browse/JDK-8027682.

MOE_MIGRATED_REVID=145835186

Author: cushon

core/src/main/java/com/google/googlejavaformat/java/JavaInputAstVisitor.java

@@ -342,6 +342,11 @@ public Void visitCompilationUnit(CompilationUnitTree node, Void unused) {
     }
     dropEmptyDeclarations();
     for (Tree type : node.getTypeDecls()) {
+      if (type.getKind() == Tree.Kind.IMPORT) {
+        // javac treats extra semicolons in the import list as type declarations
+        // TODO(cushon): remove this if https://bugs.openjdk.java.net/browse/JDK-8027682 is fixed
+        continue;
+      }
       if (!first) {
         builder.blankLineWanted(BlankLineWanted.YES);
       }
@@ -1070,6 +1075,8 @@ public Void visitImport(ImportTree node, Void unused) {
     }
     visitName(node.getQualifiedIdentifier());
     token(";");
+    // TODO(cushon): remove this if https://bugs.openjdk.java.net/browse/JDK-8027682 is fixed
+    dropEmptyDeclarations();
     return null;
   }
 

core/src/test/resources/com/google/googlejavaformat/java/testdata/B21647014.output

@@ -1,7 +1,6 @@
 package test;
 
-import java.util.List;
-;;
+import java.util.List;;;
 
 class Test {;
   public int x = 42;;;;;

core/src/test/resources/com/google/googlejavaformat/java/testdata/B28788559.input

@@ -0,0 +1,7 @@
+import a.A;;
+import b.B;
+
+class Test {
+  A a;
+  B b;
+}

core/src/test/resources/com/google/googlejavaformat/java/testdata/B28788559.output

@@ -0,0 +1,7 @@
+import a.A;;
+import b.B;
+
+class Test {
+  A a;
+  B b;
+}