Cherry pick "StrictMode warning reading command line file."

Cherry pick I659d8b42459bfecc299374b774405e952a74bf2d to
master-chromium.

Change-Id: If30edb8c324dada8ed99da400a5f9c5fab89f938
diff --git a/chromium/java/com/android/webview/chromium/WebViewChromiumFactoryProvider.java b/chromium/java/com/android/webview/chromium/WebViewChromiumFactoryProvider.java
index d24df5c..c688d44 100644
--- a/chromium/java/com/android/webview/chromium/WebViewChromiumFactoryProvider.java
+++ b/chromium/java/com/android/webview/chromium/WebViewChromiumFactoryProvider.java
@@ -26,6 +26,7 @@
 import android.os.Build;
 import android.os.FileUtils;
 import android.os.Looper;
+import android.os.StrictMode;
 import android.os.SystemProperties;
 import android.os.Trace;
 import android.util.Log;
@@ -99,7 +100,10 @@
 
     public WebViewChromiumFactoryProvider() {
         if (Build.IS_DEBUGGABLE) {
+            // Suppress the StrictMode violation as this codepath is only hit on debugglable builds.
+            StrictMode.ThreadPolicy oldPolicy = StrictMode.allowThreadDiskReads();
             CommandLine.initFromFile(COMMAND_LINE_FILE);
+            StrictMode.setThreadPolicy(oldPolicy);
         } else {
             CommandLine.init(null);
         }