[IC] Refactor IC maps to reuse code and ensure consistency

The key changes include:
  - Top interface: `PersistentStorage`
  - Implementation:
      + `LazyStorage`
      + `InMemoryStorage`
  - Extended functionality:
      + `BasicMap`
      + `PersistentStorageAdapter`

 The remaining changes are small cleanups to adapt to the above key
 changes.

 Test: Existing tests (refactoring change)
 Bug: N/A (code cleanup)

compiler/incremental-compilation-impl/test/org/jetbrains/kotlin/incremental/snapshots/FileSnapshotMapTest.kt

@@ -32,8 +32,7 @@ class FileSnapshotMapTest : TestWithWorkingDir() {
 
     @After
     override fun tearDown() {
-        snapshotMap.flush(false)
-        snapshotMap.closeForTest()
+        snapshotMap.close()
         super.tearDown()
     }
 

compiler/incremental-compilation-impl/test/org/jetbrains/kotlin/incremental/storage/SourceToOutputFilesMapTest.kt

@@ -50,8 +50,7 @@ class SourceToOutputFilesMapTest {
 
     @After
     fun tearDown() {
-        stofMap.flush(false)
-        stofMap.closeForTest()
+        stofMap.close()
     }
 
     @Test