Don't call ProcessInitializationHandler.initializePostNative() when running ServiceManager only.

All codes in ProcessInitializationHandler.initializePostNative() requires
full browser to run. And some of the class uses profile during initialization,
which will crash when only service manager is running. As a result, there is
no need to run this method if full browser is not launched.
For services, they should add their own required tasks in
ChromeBrowserInitializer.handlePostNativeStartup.

BUG=695115

Change-Id: I66f314cfcb56df00553f017d3e5b6989e3a9ef60
Reviewed-on: https://chromium-review.googlesource.com/1182008Reviewed-by: Ted Choc <tedchoc@chromium.org>
Reviewed-by: Xi Han <hanxi@chromium.org>
Commit-Queue: Min Qin <qinmin@chromium.org>
Cr-Commit-Position: refs/heads/master@{#585341}

chrome/android/java/src/org/chromium/chrome/browser/init/ChromeBrowserInitializer.java

@@ -272,12 +272,16 @@ public class ChromeBrowserInitializer {
                     + "ChromeBrowserInitializer.postInflationStartup has been run.");
         }
         final ChainedTasks tasks = new ChainedTasks();
-        tasks.add(new Runnable() {
-            @Override
-            public void run() {
-                ProcessInitializationHandler.getInstance().initializePostNative();
-            }
-        });
+        // If full browser process is not going to be launched, it is up to individual service to
+        // launch its required components.
+        if (!delegate.startServiceManagerOnly()) {
+            tasks.add(new Runnable() {
+                @Override
+                public void run() {
+                    ProcessInitializationHandler.getInstance().initializePostNative();
+                }
+            });
+        }
 
         tasks.add(new Runnable() {
             @Override