Remove request.systemInstruction validation

We only define system prompts via onDeviceParams
initialization.

Author: erikeldridge

packages/vertexai/src/methods/chrome-adapter.ts

@@ -141,25 +141,6 @@ export class ChromeAdapter {
       }
     }
 
-    if (request.systemInstruction) {
-      const systemContent = request.systemInstruction as Content;
-      // Returns false if the role can't be represented on-device.
-      if (systemContent.role && systemContent.role === 'function') {
-        return false;
-      }
-
-      // Returns false if the system prompt is multi-part.
-      if (systemContent.parts && systemContent.parts.length > 1) {
-        return false;
-      }
-
-      // Returns false if the system prompt isn't text.
-      const systemText = request.systemInstruction as TextPart;
-      if (!systemText.text) {
-        return false;
-      }
-    }
-
     return true;
   }