IDEA-123396 Multiple carets: offer completion from other caret, if primary caret has no completion variants

java/java-tests/testData/codeInsight/completion/normal/MulticaretCompletionFromNonPrimaryCaret.java

@@ -0,0 +1,4 @@
+class Foo {{
+  System.<caret>
+  System.<caret>
+}}

java/java-tests/testSrc/com/intellij/codeInsight/completion/NormalCompletionTest.groovy

@@ -1423,6 +1423,11 @@ class XInternalError {}
     checkResult()
   }
 
+  public void testMulticaretCompletionFromNonPrimaryCaret() {
+    configure()
+    myFixture.assertPreferredCompletionItems(0, "arraycopy")
+  }
+
   public void "test complete lowercase class name"() {
     myFixture.addClass("package foo; public class myClass {}")
     myFixture.configureByText "a.java", """