FIR IDE: Add visibility checks to the completion

Visibility checks currently do not work in some cases, for example:

- public nested class of private class is seen globally
- private_for_this does not work
- some other cases I am not yet aware of

If `FirVisibilityChecker.isVisible` fix those issues, they will be fixed
automatically in the completion

idea/idea-completion/testData/basic/multifile/NotImportedClass/NotImportedClass.dependency.kt

@@ -0,0 +1,13 @@
+package dependency
+
+class PublicTopLevelClass {
+    class PublicNestedClass
+    protected class ProtectedNestedClass
+    private class PrivateNestedClass
+
+    inner class PublicInnerClass
+    protected inner class ProtectedInnerClass
+    private inner class PrivateInnerClass
+}
+
+private class PrivateTopLevelClass

idea/idea-completion/testData/basic/multifile/NotImportedClass/NotImportedClass.kt

@@ -0,0 +1,7 @@
+// FIR_COMPARISON
+package test
+
+fun usage(): P<caret> {}
+
+// EXIST: PublicTopLevelClass, PublicNestedClass, PublicInnerClass
+// ABSENT: PrivateNestedClass, PrivateInnerClass, ProtectedNestedClass, ProtectedInnerClass, PrivateTopLevelClass

idea/idea-completion/testData/basic/multifile/NotImportedExtensionProperty/NotImportedExtensionProperty.dependency.kt

@@ -3,4 +3,6 @@ package abc
 val String.helloProp1: Int get() = 1
 val String.helloProp2: Int get() = 2
 val Int.helloProp3: Int get() = 3
-val helloProp4: Int = 4
+val helloProp4: Int = 4
+
+private val String.helloPropPrivate get() = 1

idea/idea-completion/testData/basic/multifile/NotImportedExtensionProperty/NotImportedExtensionProperty.kt

@@ -1,3 +1,4 @@
+// FIR_COMPARISON
 package first
 
 fun firstFun() {
@@ -5,8 +6,9 @@ fun firstFun() {
     a.hello<caret>
 }
 
-// EXIST: { lookupString: "helloProp1", attributes: "bold" }
-// EXIST: { lookupString: "helloProp2", attributes: "bold" }
+// EXIST: helloProp1
+// EXIST: helloProp2
 // ABSENT: helloProp3
 // ABSENT: helloProp4
+// ABSENT: helloPropPrivate
 // NOTHING_ELSE

idea/idea-completion/testData/basic/multifile/NotImportedFunction/NotImportedFunction.dependency.kt

@@ -6,3 +6,5 @@ fun globalFun2(): Int = 1
 object Some {
     fun globalFun3(): Int = 3
 }
+
+private fun globalFunPrivate() {}

idea/idea-completion/testData/basic/multifile/NotImportedFunction/NotImportedFunction.kt

@@ -7,3 +7,4 @@ fun testFun() {
 
 // EXIST: globalFun1, globalFun2
 // ABSENT: globalFun3
+// ABSENT: globalFunPrivate

idea/idea-completion/testData/basic/multifile/NotImportedNestedClassFromPrivateClass/NotImportedNestedClassFromPrivateClass.dependency.kt

@@ -0,0 +1,11 @@
+package dependency
+
+private class PrivateTopLevelClass {
+    class PublicNestedClass
+    protected class ProtectedNestedClass
+    private class PrivateNestedClass
+
+    inner class PublicInnerClass
+    protected inner class ProtectedInnerClass
+    private inner class PrivateInnerClass
+}

idea/idea-completion/testData/basic/multifile/NotImportedNestedClassFromPrivateClass/NotImportedNestedClassFromPrivateClass.kt

@@ -0,0 +1,13 @@
+package test
+
+fun usage(): P<caret> {}
+
+// ABSENT: PrivateTopLevelClass
+
+// ABSENT: PublicNestedClass
+// ABSENT: ProtectedNestedClass
+// ABSENT: PrivateNestedClass
+
+// ABSENT: PublicInnerClass
+// ABSENT: ProtectedInnerClass
+// ABSENT: PrivateInnerClass

idea/idea-completion/testData/basic/multifile/TopLevelFunction/TopLevelFunction.dependency.kt

@@ -1,4 +1,6 @@
 package first
 
 fun secondFun() {
-}
+}
+
+private fun secondFunPrivate() {}

idea/idea-completion/testData/basic/multifile/TopLevelFunction/TopLevelFunction.kt

@@ -5,4 +5,5 @@ fun firstFun() {
     s<caret>
 }
 
-// EXIST: secondFun
+// EXIST: secondFun
+// ABSENT: secondFunPrivate