Initial implementation of usage search for get/set methods in form of synthetic extension

idea/testData/findUsages/java/findJavaMethodUsages/SyntheticProperties.0.java

@@ -0,0 +1,6 @@
+// PSI_ELEMENT: com.intellij.psi.PsiMethod
+// OPTIONS: usages
+class JavaClass {
+    public int <caret>getSomething() { return 1; }
+    public void setSomething(int value) {}
+}