This is the test for heap snapshot comparison functionality.
To use this test:

- load file in the browser;
- open DevTools (Ctrl+Shift+I on Win/Linux, Command+Option+I on Mac);
- go to 'Profiles' page;
- press 'Take heap snapshot' button (eye icon on the left side of the status bar);
- press ;
- press 'Take heap snapshot' button again;

On the left pane under 'Heap snapshots' section, items called 'Snapshot 1' and 'Snapshot 2' must appear. Select 'Snapshot 2'. Ensure that absolute values are shown (not percents).
TEST 1. Verify the following:

- the value in '+/- Count' column for 'A' must be '-25';
- after expanding 'A' item, the value in '+/- Count' column for 'Array' child entry must also be '-25';
- the value in '+/- Count' column for 'B' must be '+25';
- after expanding 'B' item, the value in '+/- Count' column for 'Array' child entry must also be '+25'; the value for 'A' child must be '-25';

TEST 2. Change display to percent view (using the percent button on the status bar). Verify the following:

- values in '+/- Count' and '+/- Size' columns for 'C' must be 'deleted';
- values in '+/- Count' and '+/- Size' columns for 'D' must be 'new';