[EXPLORER] Add support for Windows 7 style system tray icon spacing (#5489)

When using large taskbar icon:
- Increase the padding around system tray icons.
- Push the clock text further to the right, increasing the left padding
  between the clock and notification icons.
  This matches Windows 7 shell behavior.
- Correct the spacing for the clock area, in the case when bPreferDate is
  enabled, only two lines are visible, and the day of the week is shorter
  than the date.

CORE-11698

base/shell/explorer/precomp.h

@@ -211,6 +211,7 @@ struct TaskbarSettings
     BOOL bPreferDate;
     BOOL bHideInactiveIcons;
     BOOL bSmallIcons;
+    BOOL bCompactTrayIcons;
     TW_STRUCKRECTS2 sr;
 
     BOOL Load();

base/shell/explorer/settings.cpp

@@ -32,6 +32,7 @@ BOOL TaskbarSettings::Save()
     SHSetValueW(hkExplorer, L"Advanced", L"TaskbarSizeMove", REG_DWORD, &bAllowSizeMove, sizeof(bAllowSizeMove));
     sr.cbSize = sizeof(sr);
     SHSetValueW(hkExplorer, L"Advanced", L"TaskbarSmallIcons", REG_DWORD, &bSmallIcons, sizeof(bSmallIcons));
+    SHSetValueW(hkExplorer, L"Advanced", L"CompactTrayIcons", REG_DWORD, &bCompactTrayIcons, sizeof(bCompactTrayIcons));
     SHSetValueW(hkExplorer, L"StuckRects2", L"Settings", REG_BINARY, &sr, sizeof(sr));
 
     /* TODO: AutoHide writes something to HKEY_CURRENT_USER\Software\Microsoft\Internet Explorer\Desktop\Components\0 figure out what and why */
@@ -61,6 +62,9 @@ BOOL TaskbarSettings::Load()
     dwRet = SHGetValueW(hkExplorer, L"Advanced", L"TaskbarSmallIcons", NULL, &dwValue, &cbSize);
     bSmallIcons = (dwRet == ERROR_SUCCESS) ? (dwValue != 0) : TRUE;
 
+    dwRet = SHGetValueW(hkExplorer, L"Advanced", L"CompactTrayIcons", NULL, &dwValue, &cbSize);
+    bCompactTrayIcons = (dwRet == ERROR_SUCCESS) ? (dwValue != 0) : bSmallIcons;
+
     cbSize = sizeof(sr);
     dwRet = SHGetValueW(hkExplorer, L"StuckRects2", L"Settings", NULL, &sr, &cbSize);
 

base/shell/explorer/syspager.cpp

@@ -1252,6 +1252,11 @@ void CNotifyToolbar::Initialize(HWND hWndParent, CBalloonQueue * queue)
     tbm.dwMask = TBMF_BARPAD | TBMF_BUTTONSPACING | TBMF_PAD;
     tbm.cxPad = 1;
     tbm.cyPad = 1;
+    if (!g_TaskbarSettings.bCompactTrayIcons)
+    {
+        tbm.cxPad = GetSystemMetrics(SM_CXSMICON) / 2;
+        tbm.cyPad = GetSystemMetrics(SM_CYSMICON) / 2;
+    }
     tbm.cxBarPad = 1;
     tbm.cyBarPad = 1;
     tbm.cxButtonSpacing = 1;
@@ -1397,11 +1402,19 @@ void CSysPagerWnd::GetSize(IN BOOL IsHorizontal, IN PSIZE size)
     INT columns = 0;
     INT cyButton = GetSystemMetrics(SM_CYSMICON) + 2;
     INT cxButton = GetSystemMetrics(SM_CXSMICON) + 2;
+    if (!g_TaskbarSettings.bCompactTrayIcons)
+    {
+        cyButton = MulDiv(GetSystemMetrics(SM_CYSMICON), 3, 2);
+        cxButton = MulDiv(GetSystemMetrics(SM_CXSMICON), 3, 2);
+    }
     int VisibleButtonCount = Toolbar.GetVisibleButtonCount();
 
     if (IsHorizontal)
     {
-        rows = max(size->cy / cyButton, 1);
+        if (!g_TaskbarSettings.bCompactTrayIcons)
+            rows = max(size->cy / MulDiv(cyButton, 3, 2), 1);
+        else
+            rows = max(size->cy / cyButton, 1);
         columns = (VisibleButtonCount + rows - 1) / rows;
     }
     else

base/shell/explorer/trayclock.cpp

@@ -267,6 +267,10 @@ WORD CTrayClockWnd::GetMinimumSize(IN BOOL Horizontal, IN OUT PSIZE pSize)
     if (!LinesMeasured)
         return 0;
 
+    /* Prevents the date from being cut off when the day of the week is shorter than the date. */
+    if (VisibleLines > 1 && g_TaskbarSettings.bPreferDate)
+        szMax.cx = LineSizes[CLOCKWND_FORMAT_DATE].cx;
+
     for (i = 0; i < CLOCKWND_FORMAT_COUNT; i++)
     {
         if (LineSizes[i].cx != 0)
@@ -567,8 +571,11 @@ VOID CTrayClockWnd::PaintLine(IN HDC hDC, IN OUT RECT *rcClient, IN UINT LineNum
     if (LineSizes[LineNumber].cx == 0)
         return;
 
+    INT HShift = ((IsHorizontal && (VisibleLines <= 1 ||
+                   g_TaskbarSettings.bCompactTrayIcons)) ? 0 : TRAY_CLOCK_WND_SPACING_X);
+
     TextOut(hDC,
-            (rcClient->right - LineSizes[szLinesIndex].cx) / 2,
+            ((rcClient->right - LineSizes[szLinesIndex].cx) / 2) + HShift,
             rcClient->top + TRAY_CLOCK_WND_SPACING_Y,
             szLines[szLinesIndex],
             wcslen(szLines[szLinesIndex]));