Fix inaccuracy in chrome.privacy.network.networkPredictionEnabled docs.

Bug: 785125
Change-Id: I018a94e0ea980c2971a8d085adf394cf13992fa3
Reviewed-on: https://chromium-review.googlesource.com/775141Reviewed-by: Devlin <rdevlin.cronin@chromium.org>
Commit-Queue: Matt Menke <mmenke@chromium.org>
Cr-Commit-Position: refs/heads/master@{#517184}

chrome/common/extensions/api/privacy.json

@@ -23,7 +23,7 @@
           "networkPredictionEnabled": {
             "$ref": "types.ChromeSetting",
             "value": ["networkPredictionEnabled", {"type":"boolean"}],
-            "description": "If enabled, Chrome attempts to speed up your web browsing experience by pre-resolving DNS entries, prerendering sites (<code>&lt;link rel='prefetch' ...&gt;</code>), and preemptively opening TCP and SSL connections to servers.  This preference's value is a boolean, defaulting to <code>true</code>."
+            "description": "If enabled, Chrome attempts to speed up your web browsing experience by pre-resolving DNS entries and preemptively opening TCP and SSL connections to servers. This preference only affects actions taken by Chrome's internal prediction service. It does not affect webpage-initiated prefectches or preconnects. This preference's value is a boolean, defaulting to <code>true</code>."
           },
           "webRTCMultipleRoutesEnabled": {
             "$ref": "types.ChromeSetting",