[Impeller] started asserting golden test runner has fatal impeller validations (#51357)

fixes flutter/flutter#145017

This works by removing the conditional compilation for validation and
turning them to be fatal in the test runner's main.

## Pre-launch Checklist

- [x] I read the [Contributor Guide] and followed the process outlined
there for submitting PRs.
- [x] I read the [Tree Hygiene] wiki page, which explains my
responsibilities.
- [x] I read and followed the [Flutter Style Guide] and the [C++,
Objective-C, Java style guides].
- [x] I listed at least one issue that this PR fixes in the description
above.
- [x] I added new tests to check the change I am making or feature I am
adding, or the PR is [test-exempt]. See [testing the engine] for
instructions on writing and running engine tests.
- [x] I updated/added relevant documentation (doc comments with `///`).
- [x] I signed the [CLA].
- [x] All existing and new tests are passing.

If you need help, consider asking for advice on the #hackers-new channel
on [Discord].

<!-- Links -->
[Contributor Guide]:
https://github.com/flutter/flutter/wiki/Tree-hygiene#overview
[Tree Hygiene]: https://github.com/flutter/flutter/wiki/Tree-hygiene
[test-exempt]:
https://github.com/flutter/flutter/wiki/Tree-hygiene#tests
[Flutter Style Guide]:
https://github.com/flutter/flutter/wiki/Style-guide-for-Flutter-repo
[C++, Objective-C, Java style guides]:
https://github.com/flutter/engine/blob/main/CONTRIBUTING.md#style
[testing the engine]:
https://github.com/flutter/flutter/wiki/Testing-the-engine
[CLA]: https://cla.developers.google.com/
[flutter/tests]: https://github.com/flutter/tests
[breaking change policy]:
https://github.com/flutter/flutter/wiki/Tree-hygiene#handling-breaking-changes
[Discord]: https://github.com/flutter/flutter/wiki/Chat

Author: gaaclarke

impeller/base/validation.cc

@@ -46,17 +46,22 @@ std::ostream& ValidationLog::GetStream() {
 }
 
 void ImpellerValidationBreak(const char* message) {
-// Nothing to do. Exists for the debugger.
-#ifdef IMPELLER_ENABLE_VALIDATION
   std::stringstream stream;
+#if FLUTTER_RELEASE
+  stream << "Impeller validation: " << message;
+#else
   stream << "Break on '" << __FUNCTION__
          << "' to inspect point of failure: " << message;
+#endif
   if (sValidationLogsAreFatal > 0) {
     FML_LOG(FATAL) << stream.str();
   } else {
     FML_LOG(ERROR) << stream.str();
   }
-#endif  // IMPELLER_ENABLE_VALIDATION
+}
+
+bool ImpellerValidationErrorsAreFatal() {
+  return sValidationLogsAreFatal;
 }
 
 }  // namespace impeller

impeller/base/validation.h

@@ -5,12 +5,6 @@
 #ifndef FLUTTER_IMPELLER_BASE_VALIDATION_H_
 #define FLUTTER_IMPELLER_BASE_VALIDATION_H_
 
-#ifndef IMPELLER_ENABLE_VALIDATION
-#ifdef IMPELLER_DEBUG
-#define IMPELLER_ENABLE_VALIDATION 1
-#endif
-#endif
-
 #include <sstream>
 
 namespace impeller {
@@ -39,6 +33,8 @@ void ImpellerValidationBreak(const char* message);
 
 void ImpellerValidationErrorsSetFatal(bool fatal);
 
+bool ImpellerValidationErrorsAreFatal();
+
 struct ScopedValidationDisable {
   ScopedValidationDisable();
 

impeller/golden_tests/main.cc

@@ -8,6 +8,7 @@
 #include "flutter/fml/build_config.h"
 #include "flutter/fml/command_line.h"
 #include "flutter/fml/logging.h"
+#include "flutter/impeller/base/validation.h"
 #include "flutter/impeller/golden_tests/golden_digest.h"
 #include "flutter/impeller/golden_tests/working_directory.h"
 #include "gtest/gtest.h"
@@ -24,7 +25,14 @@ void print_usage() {
 }
 }  // namespace
 
+namespace impeller {
+TEST(ValidationTest, IsFatal) {
+  EXPECT_TRUE(ImpellerValidationErrorsAreFatal());
+}
+}  // namespace impeller
+
 int main(int argc, char** argv) {
+  impeller::ImpellerValidationErrorsSetFatal(true);
   fml::InstallCrashHandler();
   testing::InitGoogleTest(&argc, argv);
   fml::CommandLine cmd = fml::CommandLineFromPlatformOrArgcArgv(argc, argv);