KT-20166: Replace type name when caret is at the end of param name

When caret is at the end ('f<caret>: Foo'), tokenAt was COLON,
not IDENTIFIER

#KT-20166 fixed

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

@@ -131,7 +131,9 @@ class KotlinCompletionContributor : CompletionContributor() {
                 }
             }
 
-            if (tokenAt.node.elementType == KtTokens.IDENTIFIER) {
+            // IDENTIFIER when 'f<caret>oo: Foo'
+            // COLON when 'foo<caret>: Foo'
+            if (tokenAt.node.elementType == KtTokens.IDENTIFIER || tokenAt.node.elementType == KtTokens.COLON) {
                 val parameter = tokenAt.parent as? KtParameter
                 if (parameter != null) {
                     context.offsetMap.addOffset(VariableOrParameterNameWithTypeCompletion.REPLACEMENT_OFFSET, parameter.endOffset)

idea/idea-completion/testData/handlers/basic/parameterNameAndType/TabReplace3.kt

@@ -0,0 +1,6 @@
+class Foo
+
+fun f(f<caret>: Foo)
+
+// ELEMENT_TEXT: foo: Foo
+// CHAR: '\t'

idea/idea-completion/testData/handlers/basic/parameterNameAndType/TabReplace3.kt.after

@@ -0,0 +1,6 @@
+class Foo
+
+fun f(foo: Foo)
+
+// ELEMENT_TEXT: foo: Foo
+// CHAR: '\t'

idea/idea-completion/tests/org/jetbrains/kotlin/idea/completion/test/handlers/BasicCompletionHandlerTestGenerated.java

@@ -698,6 +698,12 @@ public class BasicCompletionHandlerTestGenerated extends AbstractBasicCompletion
             doTest(fileName);
         }
 
+        @TestMetadata("TabReplace3.kt")
+        public void testTabReplace3() throws Exception {
+            String fileName = KotlinTestUtils.navigationMetadata("idea/idea-completion/testData/handlers/basic/parameterNameAndType/TabReplace3.kt");
+            doTest(fileName);
+        }
+
         @TestMetadata("TypeParameter.kt")
         public void testTypeParameter() throws Exception {
             String fileName = KotlinTestUtils.navigationMetadata("idea/idea-completion/testData/handlers/basic/parameterNameAndType/TypeParameter.kt");