tweak the text for the "elements didn't reload" message (#12826)

* tweak the text for the 'elements didnt reload' message

* review comments

* prefix items with a list char

* add a hostIsIde param instead of the isDaemonMode top-level function

* add a trailing comma

packages/flutter_tools/lib/src/commands/daemon.dart

@@ -372,6 +372,7 @@ class AppDomain extends Domain {
         projectRootPath: projectRootPath,
         packagesFilePath: packagesFilePath,
         projectAssets: projectAssets,
+        hostIsIde: true,
       );
     } else {
       runner = new ColdRunner(

packages/flutter_tools/lib/src/resident_runner.dart

@@ -824,7 +824,7 @@ abstract class ResidentRunner {
 }
 
 class OperationResult {
-  OperationResult(this.code, this.message, [this.hint]);
+  OperationResult(this.code, this.message, { this.hint });
 
   final int code;
   final String message;

packages/flutter_tools/lib/src/run_hot.dart

@@ -40,6 +40,7 @@ class HotRunner extends ResidentRunner {
     this.benchmarkMode: false,
     this.applicationBinary,
     this.previewDart2: false,
+    this.hostIsIde: false,
     String projectRootPath,
     String packagesFilePath,
     String projectAssets,
@@ -54,6 +55,7 @@ class HotRunner extends ResidentRunner {
              stayResident: stayResident);
 
   final String applicationBinary;
+  final bool hostIsIde;
   Set<String> _dartDependencies;
 
   final bool benchmarkMode;
@@ -452,7 +454,7 @@ class HotRunner extends ResidentRunner {
         if (result.isOk)
           printStatus('${result.message} in ${getElapsedAsMilliseconds(timer.elapsed)}.');
         if (result.hint != null)
-          printStatus(result.hint);
+          printStatus('\n${result.hint}');
         return result;
       } catch (error) {
         status.cancel();
@@ -649,28 +651,24 @@ class HotRunner extends ResidentRunner {
         unusedElements.addAll(await unusedReport);
 
       if (unusedElements.isNotEmpty) {
+        final String restartCommand = hostIsIde ? '' : ' (by pressing "R")';
         unusedElementMessage =
-          '\nThe following program elements were changed by the reload, '
-          'but did not run when the view was reassembled. If this code '
-          'only runs at start-up, you will need to restart ("R") for '
-          'the changes to have an effect.';
+          'Some program elements were changed during reload but did not run when the view was reassembled;\n'
+          'you may need to restart the app$restartCommand for the changes to have an effect.';
         for (ProgramElement unusedElement in unusedElements) {
           final String name = unusedElement.qualifiedName;
           final String path = _uriToRelativePath(unusedElement.uri);
           final int line = unusedElement.line;
-          String elementDescription;
-          if (line == null)
-            elementDescription = '$name ($path)';
-          else
-            elementDescription = '$name ($path:$line)';
-          unusedElementMessage += '\n - $elementDescription';
+          final String description = line == null ? '$name ($path)' : '$name ($path:$line)';
+          unusedElementMessage += '\n  • $description';
         }
       }
     }
 
     return new OperationResult(
       reassembleAndScheduleErrors ? 1 : OperationResult.ok.code,
-      reloadMessage, unusedElementMessage
+      reloadMessage,
+      hint: unusedElementMessage,
     );
   }
 

packages/flutter_tools/lib/src/vmservice.dart

@@ -906,9 +906,9 @@ class HeapSpace extends ServiceObject {
   }
 }
 
-// A function, field or class along with its source location.
+/// A function, field or class along with its source location.
 class ProgramElement {
-  ProgramElement(this.qualifiedName, this.uri, this.line, this.column);
+  ProgramElement(this.qualifiedName, this.uri, [this.line, this.column]);
 
   final String qualifiedName;
   final Uri uri;
@@ -1091,7 +1091,7 @@ class Isolate extends ServiceObjectOwner {
         }
       }
     }
-    return new ProgramElement(name, uri, null, null);
+    return new ProgramElement(name, uri);
   }
 
   // Lists program elements changed in the most recent reload that have not