Fix completion of 'else' keyword

#KT-14665 fixed

idea/idea-completion/src/org/jetbrains/kotlin/idea/completion/KeywordCompletion.kt

@@ -216,6 +216,10 @@ object KeywordCompletion {
                             }
                         }
 
+                        if (prevLeaf?.getParentOfType<KtIfExpression>(strict = false) != null) {
+                            prefixText += "if(true){}"
+                        }
+
                         return buildFilterWithContext(prefixText, prevParent, position)
                     }
                     else {

idea/idea-completion/testData/keywords/ElseAfterBlocklessIf.kt

@@ -0,0 +1,8 @@
+fun foo(p: Int) {
+    var x = 0
+    if (p > 0)
+        x += p
+    el<caret>
+}
+
+//EXIST: else

idea/idea-completion/testData/keywords/ElseOnOtherLine.kt

@@ -0,0 +1,8 @@
+fun foo(p: Int) {
+    if (p > 0) {
+
+    }
+    el<caret>
+}
+
+//EXIST: else

idea/idea-completion/tests/org/jetbrains/kotlin/idea/completion/test/KeywordCompletionTestGenerated.java

@@ -144,6 +144,18 @@ public class KeywordCompletionTestGenerated extends AbstractKeywordCompletionTes
         doTest(fileName);
     }
 
+    @TestMetadata("ElseAfterBlocklessIf.kt")
+    public void testElseAfterBlocklessIf() throws Exception {
+        String fileName = KotlinTestUtils.navigationMetadata("idea/idea-completion/testData/keywords/ElseAfterBlocklessIf.kt");
+        doTest(fileName);
+    }
+
+    @TestMetadata("ElseOnOtherLine.kt")
+    public void testElseOnOtherLine() throws Exception {
+        String fileName = KotlinTestUtils.navigationMetadata("idea/idea-completion/testData/keywords/ElseOnOtherLine.kt");
+        doTest(fileName);
+    }
+
     @TestMetadata("FileKeyword.kt")
     public void testFileKeyword() throws Exception {
         String fileName = KotlinTestUtils.navigationMetadata("idea/idea-completion/testData/keywords/FileKeyword.kt");