aura: Put pinch-to-zoom behind a flag (--enable-pinch or --enable-viewport)

content/public/common/content_switches.cc

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "content/public/common/content_switches.h"
 
 namespace switches {
 
 // By default, file:// URIs cannot read other file:// URIs. This is an
 // override for developers who need the old behavior for testing.
@@ skipping 259 matching lines @@
 // This does NOT enable color management for images. The source is still
 // assumed to be sRGB.
 const char kEnableMonitorProfile[]          = "enable-monitor-profile";
 
 // Enables TLS domain bound certificate extension.
 const char kEnableOriginBoundCerts[]  = "enable-origin-bound-certs";
 
 // Enables partial swaps in the WK compositor on platforms that support it.
 const char kEnablePartialSwap[]             = "enable-partial-swap";
 
+// Enables touch-screen pinch gestures.
+const char kEnablePinch[]                   = "enable-pinch";
+
 // Enable caching of pre-parsed JS script data.  See http://crbug.com/32407.
 const char kEnablePreparsedJsCaching[]      = "enable-preparsed-js-caching";
 
 // Enable privileged WebGL extensions; without this switch such extensions are
 // available only to Chrome extensions.
 const char kEnablePrivilegedWebGLExtensions[] =
     "enable-privileged-webgl-extensions";
 
 // Aggressively free GPU command buffers belonging to hidden tabs.
 const char kEnablePruneGpuCommandBuffers[] =
@@ skipping 39 matching lines @@
 
 // Enable use of experimental TCP sockets API for sending data in the
 // SYN packet.
 const char kEnableTcpFastOpen[]             = "enable-tcp-fastopen";
 
 // Enables support for video tracks. Current implementation is
 // incomplete and this flag is used for development and testing.
 const char kEnableVideoTrack[]              = "enable-video-track";
 
 // Enables the use of the viewport meta tag, which allows
-// pages to control aspects of their own layout.
+// pages to control aspects of their own layout. This also turns on touch-screen
+// pinch gestures.
 const char kEnableViewport[]                = "enable-viewport";
 
 // Enables experimental features for the geolocation API.
 // Current features:
 // - CoreLocation support for Mac OS X 10.6
 // - Gateway location for Linux and Windows
 // - Location platform support for Windows 7
 const char kExperimentalLocationFeatures[]  = "experimental-location-features";
 
 // Load NPAPI plugins from the specified directory.
@@ skipping 276 matching lines @@
 extern const char kFlingTapSuppressMaxDown[] = "fling-tap-suppress-max-down";
 
 // Maximum time between mousedown and mouseup to be considered a tap.
 extern const char kFlingTapSuppressMaxGap[] = "fling-tap-suppress-max-gap";
 
 // Forces usage of the test compositor. Needed to run ui tests on bots.
 extern const char kTestCompositor[]         = "test-compositor";
 #endif
 
 }  // namespace switches