Don't crash with a buffer underflow when packageCount == 0

[paulo-raca]

This fixes #125

I don't normally see this issue, the particular exception is on com.citymapper.app.release,
versionCode 1009500, inside split_kyc2.config.xxxhdpi

[AndroidDeveloperLB]

Wait why does it occur? Did you run the sample app I've put against the APK files I've attached?

How did you find the cause and the fix? Is it now completely fixed?

[paulo-raca]

Did you run the sample app I've put against the APK files I've attached?

Apologies for being dumb, but what sample app? Attached where?

However I did run mvn test

How did you find the cause and the fix? Is it now completely fixed?

I debugged ResourceTableParser.parse() and found that:

• resources.arsc is really small (40 bytes)
• resourceTableHeader.getPackageCount() is zero
• The string pool is empty
• It reaches the end of buffer right before reading packageHeader.

Considering there are zero packages, it seemed reasonable to skip reading packageHeader, and it fixes the problem to me.

[paulo-raca]

Oh, the problematic apks.zip attached to #125!
I Just tested them, they work fine now :)

[AndroidDeveloperLB]

I see. Can you please check the other issues I've reported, too?
Here:
#99
#108
#119
#122
#123

[AndroidDeveloperLB]

I don't see a crash on split_kyc2.config.xxxhdpi . Attached here:

split_kyc2.config.xxxhdpi.apk.zip

Can you make a sample to show that it crashes, using the official repository?