build: fix sourcemaps for dev-app and e2e-app. (#2753)

* Fixes the invalid sourcemaps for the dev-app and e2e-app.

> The sourcemaps didn't include the content of the source file because the paths were mapped incorrectly (due to a combination of `outDir` and `mapRoot`)

Author: devversion

src/demo-app/tsconfig.json

@@ -4,7 +4,6 @@
     "emitDecoratorMetadata": true,
     "experimentalDecorators": true,
     "lib": ["es6", "es2015", "dom"],
-    "mapRoot": "/",
     "module": "commonjs",
     "moduleResolution": "node",
     "noEmitOnError": true,

src/e2e-app/tsconfig.json

@@ -4,7 +4,6 @@
     "emitDecoratorMetadata": true,
     "experimentalDecorators": true,
     "lib": ["es6", "es2015", "dom"],
-    "mapRoot": "",
     "module": "commonjs",
     "moduleResolution": "node",
     "noEmitOnError": true,

src/lib/tsconfig-srcs.json

@@ -4,7 +4,6 @@
     "emitDecoratorMetadata": true,
     "experimentalDecorators": true,
     "lib": ["es6", "es2015", "dom"],
-    "mapRoot": "",
     "module": "es2015",
     "moduleResolution": "node",
     "noEmitOnError": true,

src/lib/tsconfig.json

@@ -4,7 +4,6 @@
     "emitDecoratorMetadata": true,
     "experimentalDecorators": true,
     "lib": ["es6", "es2015", "dom"],
-    "mapRoot": "",
     "module": "commonjs",
     "moduleResolution": "node",
     "noEmitOnError": true,