[Analysis API] Add source shadowing for resolve extensions.

KtResolveExtensions are designed to handle IDE analysis use cases where
source might not be available at analysis time, because that source is
generated by an external source generator, such as an annotation
processor or resource compiler. The sources generated by those external
generators can appear in the analysis scope, and cause issues with
source clash - resolution may find the virtual source from the
KtResolveExtension, the on-disk generated source from the external
generator, or both. This can cause issues, because that on-disk
generated source may be stale, and may not have symbols that will exist
the next time the generator is run (or, conversely, may have symbols
that will disappear on the next build).

To solve this, add a `getShadowedScope(): GlobalSearchScope` to
`KtResolveExtension`. Any files in the module that are included in that
scope will be hidden from resolution, allowing the resolve extension to
cleanly replace those files.

^KT-58834 fixed

analysis/analysis-api/testData/resolveExtensions/multiModule/referenceResolve/extendedModuleDependency/shadowedDeclaration.kt

@@ -0,0 +1,15 @@
+// UNRESOLVED_REFERENCE
+
+// MODULE: extendedModule
+// FILE: declarations.hidden.kt
+package foo
+
+fun bar() = "baz"
+
+// MODULE: dependency2
+
+// MODULE: main(extendedModule, dependency2)()()
+// FILE: main.kt
+fun main() {
+    val x = foo.<caret>bar()
+}

analysis/analysis-api/testData/resolveExtensions/multiModule/referenceResolve/extendedModuleDependency/shadowedJava.kt

@@ -0,0 +1,19 @@
+// UNRESOLVED_REFERENCE
+
+// MODULE: extendedModule
+// FILE: TestClass.hidden.java
+package foo;
+
+public class TestClass {
+    public TestClass() {}
+}
+
+// MODULE: dependency2
+
+// MODULE: main(extendedModule, dependency2)()()
+// FILE: main.kt
+package foo
+
+fun main() {
+    val x = <caret>TestClass()
+}

analysis/analysis-api/testData/resolveExtensions/multiModule/referenceResolve/extendedModuleDependency/shadowedOverload.kt

@@ -0,0 +1,15 @@
+// MODULE: extendedModule
+// FILE: generated.hidden.kt
+package generated
+
+fun String.generatedOverloadedExtensionFunction(): Int = TODO()
+
+// MODULE: dependency2
+
+// MODULE: main(extendedModule, dependency2)()()
+// FILE: main.kt
+import generated.*
+
+fun main() {
+    "string".generatedOverloadedExtension<caret>Function()
+}

analysis/analysis-api/testData/resolveExtensions/multiModule/referenceResolve/extendedModuleDependency/shadowedOverload.txt

@@ -0,0 +1,2 @@
+Resolved to:
+0: (in generated) fun kotlin.Any.generatedOverloadedExtensionFunction(): kotlin.Int