Align Severity enum used for checks with the Severity that we use for…

… style guides. (#1025)

cmd/registry/cmd/check/rules/rule111/rule111.go

@@ -90,7 +90,7 @@ var mimeTypeContents = &lint.FieldRule{
 		detectedType, _, _ := mime.ParseMediaType(detected)
 		if declaredType != detectedType {
 			return []*rpc.Problem{{
-				Severity:   rpc.Problem_WARN,
+				Severity:   rpc.Problem_WARNING,
 				Message:    fmt.Sprintf("Unexpected mime_type %q for contents.", declared),
 				Suggestion: fmt.Sprintf("Detected mime_type: %q.", detected),
 			}}

cmd/registry/cmd/check/rules/rule111/rule111_test.go

@@ -63,7 +63,7 @@ func TestMimeTypeContents(t *testing.T) {
 			[]*rpc.Problem{{
 				Message:    `Unexpected mime_type "text/html" for contents.`,
 				Suggestion: `Detected mime_type: "text/plain; charset=utf-8".`,
-				Severity:   rpc.Problem_WARN,
+				Severity:   rpc.Problem_WARNING,
 			}},
 		},
 		{

google/cloud/apigeeregistry/v1/check/check_report.proto

@@ -64,16 +64,21 @@ message Problem {
   // RuleDocUri provides a uri to the documented explaination of this rule.
   string rule_doc_uri = 6;
 
-  // Possible states for this guideline.
+  // Possible severities for the violation of a rule.
   enum Severity {
     // The default value, unused.
     SEVERITY_UNSPECIFIED = 0;
-    // This is a note.
-    INFO = 1;
-    // This is a strong recommendation.
-    WARN = 2;
-    // This is an issue and should be resolved.
-    ERROR = 3;
+    // Violation of the rule is an error that must be fixed.
+    ERROR = 1;
+    // Violation of the rule is a pattern that is wrong,
+    // and should be warned about.
+    WARNING = 2;
+    // Violation of the rule is not necessarily a bad pattern
+    // or error, but information the user should be aware of.
+    INFO = 3;
+    // Violation of the rule is a hint that is provided to
+    // the user to fix their spec's design.
+    HINT = 4;
   }
 
 	// Severity provides information on the criticality of the Problem.