Fix NPE on start-up when no application class exists in ApplicationInfo

base/android/java/src/org/chromium/base/library_loader/Linker.java

Index: base/android/java/src/org/chromium/base/library_loader/Linker.java
diff --git a/base/android/java/src/org/chromium/base/library_loader/Linker.java b/base/android/java/src/org/chromium/base/library_loader/Linker.java
index e6f72bc880f1931e48be97a3a7e82b1002828a4f..271e6cb7848d7aa40258efa075ccf871e43e5b0a 100644
--- a/base/android/java/src/org/chromium/base/library_loader/Linker.java
+++ b/base/android/java/src/org/chromium/base/library_loader/Linker.java
@@ -244,7 +244,8 @@ public abstract class Linker {
                 // library loading path in order for the libraries to be found.
                 String appClass =
                         ContextUtils.getApplicationContext().getApplicationInfo().className;
-                boolean isIncrementalInstall = appClass.contains("incrementalinstall");
+                boolean isIncrementalInstall =
+                        appClass != null && appClass.contains("incrementalinstall");
                 if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.M && !isIncrementalInstall) {
                     sSingleton = ModernLinker.create();
                 } else {