This test runs a simple looped computation to test focusing and exclusion functionality of profile view grid.
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 'Start profiling' button (gray dot on the left side of status bar);
- wait for 5 seconds;
- press 'Stop profiling' button (red dot on the left side of status bar);

On the left pane under 'CPU profiles' section, an item called 'Profile 1' must appear, and a grid with profile data must appear on the right. Now test the following functionality in the grid:
TEST 1:

- select 'eternal_fib' function entry (without expanding it), press 'Focus on selected function' button (eye on the right of the status bar);
- ensure that only 'eternal_fib' function and its children are left in the tree, and 'Total' column for the function shows '100%' value;
- expand 'eternal_fib' function node;
- press 'Restore all functions' button;
- verify that the value in 'Total' column is less than 100%;
- verify that 'eternal_fib' function node is can still be collapsed and expanded back;

TEST 2:

- expand two levels of 'Script:' node, select the second-level node;
- repeat the same steps for the selected node (in this case, immediate parent nodes of the focused node must also remain visible after focusing);

TEST 3:

- by expanding 'Script:' node, make sure that at least 3 'eternal_fib' function nodes are visible;
- select any of 'eternal_fib' nodes and press 'Exclude selected function' (cross) button on the status bar;
- verify that all 'eternal_fib' nodes are no more visible;
- expand more 'Script:' node levels, verify that no new 'eternal_fib' nodes appear with expansion;
- press 'Restore all functions' button;
- verify that 'eternal_fib' nodes are now visible;

TESTS 4 and 5:
Now switch to 'Tree (Top Down)' view and repeat testing steps. For the 'Exclude selected function' function test, use 'Script:' function node, as 'eternal_fib' has only one entry in this view.