Make name: and code: required parameters in the canvas test generator

In the process of documenting the test generator, it's useful to clarify
which parameters are required and which ones are optional. The only two
required parameters are 'name:' and 'code:'.

Bug: 393561071
Change-Id: I89c0fa7cc9bd0a8923a4320c5e02ac9e5f81a9e0
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/6219870
Reviewed-by: Andres Ricardo Perez <[email protected]>
Commit-Queue: Jean-Philippe Gravel <[email protected]>
Cr-Commit-Position: refs/heads/main@{#1423203}

Author: graveljp

html/canvas/tools/gentest.py

@@ -441,6 +441,11 @@ def mkdir(self) -> None:
 
 
 def _validate_test(test: _TestParams):
+    for param in ['name', 'code']:
+        if test.get(param) is None:
+            raise InvalidTestDefinitionError(
+                f'Test parameter "{param}" must be specified.')
+
     if test.get('expected', '') == 'green' and re.search(
             r'@assert pixel .* 0,0,0,0;', test['code']):
         print(f'Probable incorrect pixel test in {test["name"]}')