fix(ivy): don't run decorator handlers against declaration files (#34557)

Currently the decorator handlers are run against all `SourceFile`s in the compilation, but we shouldn't be doing it against declaration files. This initially came up as a CI issue in #33264 where it was worked around only for the `DirectiveDecoratorHandler`. These changes move the logic into the `TraitCompiler` and `DecorationAnalyzer` so that it applies to all of the handlers.

PR Close #34557

packages/compiler-cli/ngcc/test/analysis/decoration_analyzer_spec.ts

@@ -11,7 +11,7 @@ import {FatalDiagnosticError, makeDiagnostic} from '../../../src/ngtsc/diagnosti
 import {absoluteFrom, getFileSystem, getSourceFileOrError} from '../../../src/ngtsc/file_system';
 import {TestFile, runInEachFileSystem} from '../../../src/ngtsc/file_system/testing';
 import {ClassDeclaration, Decorator} from '../../../src/ngtsc/reflection';
-import {DecoratorHandler, DetectResult} from '../../../src/ngtsc/transform';
+import {AnalysisOutput, CompileResult, DecoratorHandler, DetectResult, HandlerPrecedence} from '../../../src/ngtsc/transform';
 import {loadFakeCore, loadTestFiles} from '../../../test/helpers';
 import {DecorationAnalyzer} from '../../src/analysis/decoration_analyzer';
 import {NgccReferencesRegistry} from '../../src/analysis/ngcc_references_registry';
@@ -392,6 +392,29 @@ runInEachFileSystem(() => {
              expect(diagnosticLogs[1]).toEqual(jasmine.objectContaining({code: -999998}));
            });
       });
+
+      describe('declaration files', () => {
+        it('should not run decorator handlers against declaration files', () => {
+          class FakeDecoratorHandler implements DecoratorHandler<{}|null, unknown, unknown> {
+            name = 'FakeDecoratorHandler';
+            precedence = HandlerPrecedence.PRIMARY;
+
+            detect(): undefined { throw new Error('detect should not have been called'); }
+            analyze(): AnalysisOutput<unknown> {
+              throw new Error('analyze should not have been called');
+            }
+            compile(): CompileResult { throw new Error('compile should not have been called'); }
+          }
+
+          const analyzer = setUpAnalyzer([{
+            name: _('/node_modules/test-package/index.d.ts'),
+            contents: 'export declare class SomeDirective {}',
+          }]);
+          analyzer.handlers = [new FakeDecoratorHandler()];
+          result = analyzer.analyzeProgram();
+          expect(result.size).toBe(0);
+        });
+      });
     });
   });
 });