TS/JS: Use TypeError instead of Error when appropriate

ts/builder.ts

@@ -268,7 +268,7 @@ export class Builder {
      */
     nested(obj: Offset): void {
       if (obj != this.offset()) {
-        throw new Error('FlatBuffers: struct must be serialized inline.');
+        throw new TypeError('FlatBuffers: struct must be serialized inline.');
       }
     }
 
@@ -278,7 +278,7 @@ export class Builder {
      */
     notNested(): void {
       if (this.isNested) {
-        throw new Error('FlatBuffers: object serialization must not be nested.');
+        throw new TypeError('FlatBuffers: object serialization must not be nested.');
       }
     }
 
@@ -429,7 +429,7 @@ export class Builder {
         this.prep(this.minalign, SIZEOF_INT +
           FILE_IDENTIFIER_LENGTH + size_prefix);
         if (file_identifier.length != FILE_IDENTIFIER_LENGTH) {
-          throw new Error('FlatBuffers: file identifier must be length ' +
+          throw new TypeError('FlatBuffers: file identifier must be length ' +
             FILE_IDENTIFIER_LENGTH);
         }
         for (let i = FILE_IDENTIFIER_LENGTH - 1; i >= 0; i--) {
@@ -463,7 +463,7 @@ export class Builder {
 
       // If this fails, the caller will show what field needs to be set.
       if (!ok) {
-        throw new Error('FlatBuffers: field ' + field + ' must be set');
+        throw new TypeError('FlatBuffers: field ' + field + ' must be set');
       }
     }
 
@@ -576,7 +576,7 @@ export class Builder {
         if(val !== null) {
           ret.push(this.createObjectOffset(val));
         } else {
-          throw new Error(
+          throw new TypeError(
             'FlatBuffers: Argument for createObjectOffsetList cannot contain null.'); 
         }
       }