Optimize isReferenceTo() when searching for PsiMethod usages

Avoid resolving references when we know from context that a reference
at given location can't resolve to a PsiMethod.

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

@@ -0,0 +1,7 @@
+// PSI_ELEMENT: com.intellij.psi.PsiMethod
+// OPTIONS: usages
+public class UnaryNot {
+    public UnaryNot <caret>not() {
+        return this;
+    }
+}

idea/testData/findUsages/java/findJavaMethodUsages/UnaryNot.1.kt

@@ -0,0 +1,4 @@
+fun unaryClient() {
+    val u1 = UnaryNot()
+    val u2 = !u1
+}

idea/testData/findUsages/java/findJavaMethodUsages/UnaryNot.log

@@ -0,0 +1,7 @@
+Checked type of u1
+Checked type of u2
+Resolved !u1
+Searched references to UnaryNot
+Searched references to UnaryNot.not() in non-Java files
+Searched references to u1 in non-Java files
+Searched references to u2 in non-Java files

idea/testData/findUsages/java/findJavaMethodUsages/UnaryNot.results.txt

@@ -0,0 +1 @@
+Function call 3 val u2 = !u1