fix(shell): handle stdout/stderr stream error

Without this, the 'error' event is unhandled, which results in the
process dying. Print the error and move on.

Added because of 'write after end' stream error from shelling out
Angular CLI. Possibly revert pending this issue: angular/angular-cli#10922

Author: imhoffd

packages/@ionic/cli-utils/src/lib/shell.ts

@@ -2,7 +2,7 @@ import * as path from 'path';
 import { ChildProcess } from 'child_process';
 
 import chalk from 'chalk';
-
+import * as Debug from 'debug';
 import * as split2 from 'split2';
 
 import { ERROR_SHELL_COMMAND_NOT_FOUND, LOGGER_LEVELS, ShellCommandError } from '@ionic/cli-framework';
@@ -14,6 +14,8 @@ import { ILogger, IShell, IShellOutputOptions, IShellRunOptions, IShellSpawnOpti
 import { isExitCodeException } from '../guards';
 import { FatalException } from './errors';
 
+const debug = Debug('ionic:cli-utils:lib:shell');
+
 export interface ShellDeps {
   log: ILogger;
   projectDir?: string;
@@ -45,11 +47,25 @@ export class Shell implements IShell {
       const promise = cmd.run();
 
       if (promise.p.stdout) {
-        promise.p.stdout.pipe(combineStreams(split2(), ws));
+        const stream = combineStreams(split2(), ws);
+
+        // TODO: https://github.com/angular/angular-cli/issues/10922
+        stream.on('error', (err: Error) => {
+          debug('Error in subprocess stdout pipe: %o', err);
+        });
+
+        promise.p.stdout.pipe(stream);
       }
 
       if (promise.p.stderr) {
-        promise.p.stderr.pipe(combineStreams(split2(), ws));
+        const stream = combineStreams(split2(), ws);
+
+        // TODO: https://github.com/angular/angular-cli/issues/10922
+        stream.on('error', (err: Error) => {
+          debug('Error in subprocess stderr pipe: %o', err);
+        });
+
+        promise.p.stderr.pipe(stream);
       }
 
       if (killOnExit) {