do not throw if ast not present

libs/remix-debug/src/solidity-decoder/internalCallTree.ts

@@ -82,6 +82,7 @@ export class InternalCallTree {
       if (!compResult) {
         this.event.trigger('noCallTreeAvailable', [])
       } else {
+        try {
           buildTree(this, 0, scopeId, isCreation).then((result) => {
             if (result.error) {
               this.event.trigger('callTreeBuildFailed', [result.error])
@@ -94,6 +95,9 @@ export class InternalCallTree {
             console.log('analyzing trace falls ' + reason)
             this.event.trigger('callTreeNotReady', [reason])
           })
+        } catch (e) {
+          console.log(e)
+        }        
       }
     })
   }

libs/remix-debug/src/solidity-decoder/solidityProxy.ts

@@ -115,7 +115,7 @@ export class SolidityProxy {
       for (const source of generatedSources) {
         if (source.id === sourceLocation.file) return source.ast
       }
-    } else if (compilationResult.data.sources[file]) {
+    } else if (compilationResult.data.sources && compilationResult.data.sources[file]) {
       return compilationResult.data.sources[file].ast
     }
     return null