What causes the pop-up "To view this web content, you need to install the Java Runtime Environment"

On OSX Yosemite an annoying pop-up comes up quite often saying:

To view this web content, you need to install the Java Runtime Environment

I know the solution is to install java; however I'm wondering what's the cause for that.

A quick ps -axww tells me:

13218   ??  S      0:00.29 /System/Library/Java/Support/CoreDeploy.bundle/Contents/Download Java http://ift.tt/1BkbWyZ Java Components

I dug around and I found that there is a LaunchDaemon that references this in /System/Library/LaunchAgents/com.apple.java.InstallOnDemand.plist:

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE plist PUBLIC "-//Apple//DTD PLIST 1.0//EN" "http://ift.tt/vvUEPL">
<plist version="1.0">
<dict>
    <key>Label</key>
    <string>com.apple.java.InstallOnDemandAgent</string>
    <key>MachServices</key>
    <dict>
        <key>com.apple.java.installondemand</key>
        <true/>
    </dict>
    <key>Program</key>
    <string>/System/Library/Java/Support/CoreDeploy.bundle/Contents/Download Java http://ift.tt/1BkbWyZ Java Components</string>
    <key>RunAtLoad</key>
    <false/>
</dict>
</plist>

Does anyone know what is the purpose of all this? The pop-up appears at random times, which makes me think there's a background daemon that demands Java to run but I could not find any source for this behaviour.