Fix crash in RequiresPermissionChecker.java

Bug: 265320139
Test: atest --host error_prone_android_framework_test
Change-Id: Ia46d5e7cab4d39888c4975ded18c59d5eb918ffa

errorprone/java/com/google/errorprone/bugpatterns/android/RequiresPermissionChecker.java

@@ -412,11 +412,11 @@ public final class RequiresPermissionChecker extends BugChecker
 
     private static ParsedRequiresPermission parseRequiresPermissionRecursively(
             MethodInvocationTree tree, VisitorState state) {
-        if (ENFORCE_VIA_CONTEXT.matches(tree, state)) {
+        if (ENFORCE_VIA_CONTEXT.matches(tree, state) && tree.getArguments().size() > 0) {
             final ParsedRequiresPermission res = new ParsedRequiresPermission();
             res.allOf.add(String.valueOf(ASTHelpers.constValue(tree.getArguments().get(0))));
             return res;
-        } else if (ENFORCE_VIA_CHECKER.matches(tree, state)) {
+        } else if (ENFORCE_VIA_CHECKER.matches(tree, state) && tree.getArguments().size() > 1) {
             final ParsedRequiresPermission res = new ParsedRequiresPermission();
             res.allOf.add(String.valueOf(ASTHelpers.constValue(tree.getArguments().get(1))));
             return res;

errorprone/tests/java/com/google/errorprone/bugpatterns/android/RequiresPermissionCheckerTest.java

@@ -415,4 +415,27 @@ public class RequiresPermissionCheckerTest {
                         "}")
                 .doTest();
     }
+
+    @Test
+    public void testInvalidFunctions() {
+        compilationHelper
+                .addSourceFile("/android/annotation/RequiresPermission.java")
+                .addSourceFile("/android/annotation/SuppressLint.java")
+                .addSourceFile("/android/content/Context.java")
+                .addSourceLines("Example.java",
+                        "import android.annotation.RequiresPermission;",
+                        "import android.annotation.SuppressLint;",
+                        "import android.content.Context;",
+                        "class Foo extends Context {",
+                        "  private static final String RED = \"red\";",
+                        "  public void checkPermission() {",
+                        "  }",
+                        "  @RequiresPermission(RED)",
+                        "  // BUG: Diagnostic contains:",
+                        "  public void exampleScoped(Context context) {",
+                        "    checkPermission();",
+                        "  }",
+                        "}")
+                .doTest();
+    }
 }