If it doesn't make sense for Google to secure rights to Java, then why are they making Android, with so much Java influence, their main OS? Why aren't we running Mobile Chrome OS?
Perhaps you're saying Android is a fad this year or two, and then Chrome or other browsers take over.
One thing you can never accuse Google of is having a single view inside the company!
I think that Java-as-it-is-in-Android is a great technology, but some view it as transitional while HTML adds the capabilities needed to build a wide range of application.
Dalvik (the Android "JVM") is a layer on top of the Android operating system. The fact that it exists doesn't preclude other environments running as a layer as well. Android is here to stay, but I think it's a given that the capabilities of the operating system will expand. For example, Android 3.0 adds RenderScript [1], which doesn't have a Java dependency at all.
Perhaps you're saying Android is a fad this year or two, and then Chrome or other browsers take over.