build(bazel): Turning on strictPropertyInitialization for Angular. (#24572)

All errors for existing fields have been detected and suppressed with a
`!` assertion.

Issue/24571 is tracking proper clean up of those instances.

One-line change required in ivy/compilation.ts, because it appears that
the new syntax causes tsickle emitted node to no longer track their
original sourceFiles.

PR Close #24572

packages/compiler-cli/test/diagnostics/mocks.ts

@@ -117,12 +117,14 @@ const summaryResolver = new AotSummaryResolver(
 
 export class DiagnosticContext {
   // tslint:disable
-  _analyzedModules: NgAnalyzedModules;
+  // TODO(issue/24571): remove '!'.
+  _analyzedModules !: NgAnalyzedModules;
   _staticSymbolResolver: StaticSymbolResolver|undefined;
   _reflector: StaticReflector|undefined;
   _errors: {e: any, path?: string}[] = [];
   _resolver: CompileMetadataResolver|undefined;
-  _refletor: StaticReflector;
+  // TODO(issue/24571): remove '!'.
+  _refletor !: StaticReflector;
   // tslint:enable
 
   constructor(

packages/compiler-cli/test/metadata/typescript.mocks.ts

@@ -102,7 +102,8 @@ export class MockNode implements ts.Node {
 
 export class MockIdentifier extends MockNode implements ts.Identifier {
   public text: string;
-  public escapedText: ts.__String;
+  // TODO(issue/24571): remove '!'.
+  public escapedText !: ts.__String;
   // tslint:disable
   public _declarationBrand: any;
   public _primaryExpressionBrand: any;
@@ -139,7 +140,8 @@ export class MockVariableDeclaration extends MockNode implements ts.VariableDecl
 }
 
 export class MockSymbol implements ts.Symbol {
-  public escapedName: ts.__String;
+  // TODO(issue/24571): remove '!'.
+  public escapedName !: ts.__String;
   constructor(
       public name: string, private node: ts.Declaration = MockVariableDeclaration.of(name),
       public flags: ts.SymbolFlags = 0) {}