[wasm] Some cleanup of targets, especially around profiler use (#46958)

* [wasm] samples: makefile cleanup

* [wasm] Mark FileWrites as Output

* [wasm] Move driver-gen.c generation for and profile, !aot case to separate target

* [wasm] Add $(WasmProfilers) for aot compiler

* [wasm] update public properties/items list in WasmApp.targets

* wasmapp.targets - some more cleanup - differentiate internal properties

* [wasm] fix MonoAOTCompiler build error

* [wasm] WasmApp.targets - Add `WasmExtraConfig`, to add to `mono-config.js`

`WasmAppBuilder.EnableProfiler` was added to add a special entry to
`mono-config.js` (`config.enable_profiler=true`), for the
`browser-profile` sample. Instead of doing that, add a general way to
add extra json elements to the config file.

This can be done through `WasmAppBuilder.ExtraConfig` set via
`@(WasmExtraConfig)`. Examples:

```xml
    <WasmExtraConfig Include="enable_profiler" Value="true" />

    <!-- Value attribute can have a number, bool, quoted string, or json string -->

    <WasmExtraConfig Include="json" Value="{ &quot;abc&quot;: 4 }" />
    <WasmExtraConfig Include="string_val" Value="&quot;abc&quot;" />
    <WasmExtraConfig Include="string_with_json" Value="&quot;{ &quot;abc&quot;: 4 }&quot;" />
```

This would add the following to the config file:

```json
  "enable_profiler": true,
  "json": {
    "abc": 4
  },
  "string_val": "abc",
  "string_with_json": "{ \"abc\": 4 }"
```

* [wasm] Remove BuildAOTProfiled, and instead use AOTProfilePath only

* [wasm] Fix typo

* [wasm] MonoAOTCompiler: fix NRE

* [wasm] WasmAppBuilder.ExtraConfig: add comments

* [wasm] WasmAppBuilder - fix json escaping

1 files changed, 69 insertions, 6 deletions

diff --git a/src/tasks/WasmAppBuilder/WasmAppBuilder.cs b/src/tasks/WasmAppBuilder/WasmAppBuilder.cs
index c870de4c864..d43a09d07e6 100644
--- a/src/tasks/WasmAppBuilder/WasmAppBuilder.cs
+++ b/src/tasks/WasmAppBuilder/WasmAppBuilder.cs
@@ -9,6 +9,7 @@ using System.Diagnostics.CodeAnalysis;
 using System.IO;
 using System.Linq;
 using System.Text;
+using System.Text.Encodings.Web;
 using System.Text.Json;
 using System.Text.Json.Serialization;
 using System.Reflection;
@@ -33,8 +34,6 @@ public class WasmAppBuilder : Task
     [Required]
     public string[]? Assemblies { get; set; }
 
-    public bool EnableProfiler { get; set; }
-
     private List<string> _fileWrites = new();
 
     [Output]
@@ -51,6 +50,20 @@ public class WasmAppBuilder : Task
     public bool InvariantGlobalization { get; set; }
     public ITaskItem[]? ExtraFilesToDeploy { get; set; }
 
+    // <summary>
+    // Extra json elements to add to mono-config.js
+    //
+    // Metadata:
+    // - Value: can be a number, bool, quoted string, or json string
+    //
+    // Examples:
+    //      <WasmExtraConfig Include="enable_profiler" Value="true" />
+    //      <WasmExtraConfig Include="json" Value="{ &quot;abc&quot;: 4 }" />
+    //      <WasmExtraConfig Include="string_val" Value="&quot;abc&quot;" />
+    //       <WasmExtraConfig Include="string_with_json" Value="&quot;{ &quot;abc&quot;: 4 }&quot;" />
+    // </summary>
+    public ITaskItem[]? ExtraConfig { get; set; }
+
     private class WasmAppConfig
     {
         [JsonPropertyName("assembly_root")]
@@ -61,8 +74,8 @@ public class WasmAppBuilder : Task
         public List<object> Assets { get; } = new List<object>();
         [JsonPropertyName("remote_sources")]
         public List<string> RemoteSources { get; set; } = new List<string>();
-        [JsonPropertyName("enable_profiler")]
-        public bool EnableProfiler { get; set; } = false;
+        [JsonExtensionData]
+        public Dictionary<string, object?> Extra { get; set; } = new();
     }
 
     private class AssetEntry
@@ -231,9 +244,14 @@ public class WasmAppBuilder : Task
                 if (source != null && source.ItemSpec != null)
                     config.RemoteSources.Add(source.ItemSpec);
         }
-        if (EnableProfiler)
+
+        foreach (ITaskItem extra in ExtraConfig ?? Enumerable.Empty<ITaskItem>())
         {
-            config.EnableProfiler = true;
+            string name = extra.ItemSpec;
+            if (!TryParseExtraConfigValue(extra, out object? valueObject))
+                return false;
+
+            config.Extra[name] = valueObject;
         }
 
         string monoConfigPath = Path.Join(AppDir, "mono-config.js");
@@ -263,6 +281,51 @@ public class WasmAppBuilder : Task
         return true;
     }
 
+    private bool TryParseExtraConfigValue(ITaskItem extraItem, out object? valueObject)
+    {
+        valueObject = null;
+        string? rawValue = extraItem.GetMetadata("Value");
+        if (string.IsNullOrEmpty(rawValue))
+            return true;
+
+        if (TryConvert(rawValue, typeof(double), out valueObject) || TryConvert(rawValue, typeof(bool), out valueObject))
+            return true;
+
+        // Try parsing as a quoted string
+        if (rawValue!.Length > 1 && rawValue![0] == '"' && rawValue![^1] == '"')
+        {
+            valueObject = rawValue![1..^1];
+            return true;
+        }
+
+        // try parsing as json
+        try
+        {
+            JsonDocument jdoc = JsonDocument.Parse(rawValue);
+            valueObject = jdoc.RootElement;
+            return true;
+        }
+        catch (JsonException je)
+        {
+            Log.LogError($"ExtraConfig: {extraItem.ItemSpec} with Value={rawValue} cannot be parsed as a number, boolean, string, or json object/array: {je.Message}");
+            return false;
+        }
+    }
+
+    private static bool TryConvert(string str, Type type, out object? value)
+    {
+        value = null;
+        try
+        {
+            value = Convert.ChangeType(str, type);
+            return true;
+        }
+        catch (Exception ex) when (ex is FormatException || ex is InvalidCastException || ex is OverflowException)
+        {
+            return false;
+        }
+    }
+
     private bool FileCopyChecked(string src, string dst, string label)
     {
         if (!File.Exists(src))