fire tab switcher / manager sources pixel (#3722)

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Task/Issue URL:
https://app.asana.com/0/392891325557410/1208882840835128/f
Tech Design URL:
CC:

**Description**:
Fires a pixel depending on what is going on when the user opens the tab
switcher.

Also renames a couple of pixels for clarity.

**Steps to test this PR**: 

1. Open the tab switcher from anywhere should fire
`m_tab_manager_opened_daily` but only the first time during in a day
2. Open the tab switcher from anywhere should fire
`m_tab_manager_opened` every time
1. Open the tab switcher on the new tab page should fire
`m_tab_manager_open_from_newtabpage` every time
2. Open the tab switcher while on the serp should fire
`m_tab_manager_open_from_serp` every time
3. Open the tab switcher while on a website should fire
`m_tab_manager_open_from_website` every time

Core/PixelEvent.swift

@@ -60,7 +60,11 @@ extension Pixel {
         case tabSwitcherClickCloseTab
         case tabSwitcherSwipeCloseTab
         case tabSwitchLongPressNewTab
-        case tabSwitcherOpenDaily
+        case tabSwitcherOpenedDaily
+
+        case tabSwitcherOpenedFromSerp
+        case tabSwitcherOpenedFromWebsite
+        case tabSwitcherOpenedFromNewTabPage
 
         case settingsDoNotSellShown
         case settingsDoNotSellOn
@@ -118,7 +122,7 @@ extension Pixel {
         case tabBarForwardPressed
         case bookmarksButtonPressed
         case tabBarBookmarksLongPressed
-        case tabBarTabSwitcherPressed
+        case tabBarTabSwitcherOpened
 
         case homeScreenShown
         case homeScreenEditFavorite
@@ -984,7 +988,11 @@ extension Pixel.Event {
         case .tabSwitcherClickCloseTab: return "m_tab_manager_close_tab_click"
         case .tabSwitcherSwipeCloseTab: return "m_tab_manager_close_tab_swipe"
         case .tabSwitchLongPressNewTab: return "m_tab_manager_long_press_new_tab"
-        case .tabSwitcherOpenDaily: return "m_tab_manager_clicked_daily"
+        case .tabSwitcherOpenedDaily: return "m_tab_manager_opened_daily"
+
+        case .tabSwitcherOpenedFromSerp: return "m_tab_manager_open_from_serp"
+        case .tabSwitcherOpenedFromWebsite: return "m_tab_manager_open_from_website"
+        case .tabSwitcherOpenedFromNewTabPage: return "m_tab_manager_open_from_newtabpage"
 
         case .settingsDoNotSellShown: return "ms_dns"
         case .settingsDoNotSellOn: return "ms_dns_on"
@@ -1064,7 +1072,7 @@ extension Pixel.Event {
         case .tabBarForwardPressed: return "mt_fw"
         case .bookmarksButtonPressed: return "mt_bm"
         case .tabBarBookmarksLongPressed: return "mt_bl"
-        case .tabBarTabSwitcherPressed: return "mt_tb"
+        case .tabBarTabSwitcherOpened: return "m_tab_manager_opened"
 
         case .bookmarkLaunchList: return "m_bookmark_launch_list"
         case .bookmarkLaunchScored: return "m_bookmark_launch_scored"

DuckDuckGo/MainViewController.swift

@@ -2611,8 +2611,15 @@ extension MainViewController: TabSwitcherButtonDelegate {
     }
 
     func showTabSwitcher(_ button: TabSwitcherButton) {
-        Pixel.fire(pixel: .tabBarTabSwitcherPressed)
-        DailyPixel.fireDaily(.tabSwitcherOpenDaily, withAdditionalParameters: TabSwitcherOpenDailyPixel().parameters(with: tabManager.model.tabs))
+        Pixel.fire(pixel: .tabBarTabSwitcherOpened)
+        DailyPixel.fireDaily(.tabSwitcherOpenedDaily, withAdditionalParameters: TabSwitcherOpenDailyPixel().parameters(with: tabManager.model.tabs))
+        if currentTab?.url?.isDuckDuckGoSearch == true {
+            Pixel.fire(pixel: .tabSwitcherOpenedFromSerp)
+        } else if currentTab?.url != nil {
+            Pixel.fire(pixel: .tabSwitcherOpenedFromWebsite)
+        } else {
+            Pixel.fire(pixel: .tabSwitcherOpenedFromNewTabPage)
+        }
 
         performCancel()
         showTabSwitcher()