(This is a cherrypick of http://ag/576739)

Also, modify the IllegalArgumentException to capture the
values passed for start, end, and array.length to make
debugging easier in the unlikely event that it is thrown.
Add corresponding tests for the exceptions.

Tested:
tapas LatinImeGoogle LatinImeGoogleTests userdebug
make -j30 && \
adb install -r \
out/target/product/generic/data/app/LatinImeGoogleTests/LatinImeGoogleTests.apk && \
adb install -r \
out/target/product/generic/system/app/LatinImeGoogle/LatinImeGoogle.apk && \
adb shell am instrument -w -e class \
com.android.inputmethod.latin.utils.CollectionUtilsTests \
com.google.android.inputmethod.latin.tests/android.support.test.runner.AndroidJUnitRunner

Change-Id: I0c579ca4f4f2a9b2575aa6f8fa75e3ee4a21cf8a

Change-Id: I3a610b037d6d1431cced3ea193171108bd5a040d

This CL fixes the following compiler warnings.

- Indirect access to static member
- Access to a non-accessible member of an enclosing type
- Parameter assignment
- Method can be static
- Local variable declaration hides another field or variable
- Value of local variable is not used
- Unused import
- Unused private member
- Unnecessary 'else' statement
- Unnecessary declaration of throw exception
- Redundant type arguments
- Missing '@Override' annotation
- Unused '@SuppressWarning' annotations

Bug: 18003991
Change-Id: Icfebe753e53a2cc621848f769d6a3d7ce501ebc7

Bug: 17400259
Change-Id: Ib3511afffe1d14662e7dd14611f384689516e664

- Move util classes that are unused in AOSP
- Remove unused methods

Change-Id: Ic97fd313f1e2bafd50609d42aa3a2d090b63eafc

Change-Id: If16ef50ae73147594615d0f49d6a22621eaf1aef

Change-Id: If7c1eb7c802490f19c5d3b81d714362408daf376

Change-Id: I5cb402060946a711384ee53fa1caaeac86aa10cc

Change-Id: I1c5b27c8edf231680edb8d96f63b9d04cfc6a6fa

This change also cleans up MoreKeysPanel related stuff.

Bug: 8047165
Change-Id: I4f2211e00c7d08469a7413568db039c1c597fb3c

Change-Id: Ic4f69b4c8da33c9fca50d6829724179310c2f875

Change-Id: I6da97f6ea23578318f403bb5d64c30b1663c69ee

Change-Id: I6b4de9187e122298e5e9cd8ddc9070d062df6a89