fix(@angular/cli): use local typescriptMismatch if available

Fix #7678

Author: filipesilva

packages/@angular/cli/upgrade/version.ts

@@ -144,7 +144,8 @@ export class Version {
   }
 
   static assertTypescriptVersion(projectRoot: string) {
-    if (!CliConfig.fromGlobal().get('warnings.typescriptMismatch')) {
+    const config = CliConfig.fromProject() || CliConfig.fromGlobal();
+    if (!config.get('warnings.typescriptMismatch')) {
       return;
     }
     let compilerVersion: string, tsVersion: string;
@@ -182,7 +183,7 @@ export class Version {
 
             npm install typescript@'${currentCombo.typescript}'
 
-        To disable this warning run "ng set --global warnings.typescriptMismatch=false".
+        To disable this warning run "ng set warnings.typescriptMismatch=false".
       ` + '\n')));
     }
   }

tests/e2e/tests/misc/typescript-warning.ts

@@ -20,22 +20,33 @@ export default function () {
         throw new Error('Expected to have missing dependency error in output.');
       }
     })
+    // Warning should show.
     .then(() => npm('install', `typescript@${unsupportedTsVersion}`, '--no-save'))
     .then(() => ng('build'))
     .then((output) => {
       if (!output.stdout.match('Using this version can result in undefined behaviour')) {
         throw new Error('Expected to have typescript version mismatch warning in output.');
       }
     })
+    // Warning should be disabled with global flag.
     .then(() => ng('set', '--global', 'warnings.typescriptMismatch=false'))
     .then(() => ng('build'))
     .then((output) => {
       if (output.stdout.match('Using this version can result in undefined behaviour')) {
         throw new Error('Expected to not have typescript version mismatch warning in output.');
       }
     })
+    .then(() => ng('set', '--global', 'warnings.typescriptMismatch=true'))
+    // Warning should be disabled with local flag.
+    .then(() => ng('set', 'warnings.typescriptMismatch=false'))
+    .then(() => ng('build'))
+    .then((output) => {
+      if (output.stdout.match('Using this version can result in undefined behaviour')) {
+        throw new Error('Expected to not have typescript version mismatch warning in output.');
+      }
+    })
+    .then(() => ng('set', 'warnings.typescriptMismatch=true'))
     // Cleanup
-    .then(() => npm('install'))
-    .then(() => ng('set', '--global', 'warnings.typescriptMismatch=true'));
+    .then(() => npm('install'));
 }