From f5d1e35316fcd027e60655b7ca6ca6341ed1e0ec Mon Sep 17 00:00:00 2001
From: Wale Ogunwale <ogunwale@google.com>
Date: Thu, 22 Sep 2016 08:34:42 -0700
Subject: [PATCH] Don't take app screenshot in minimize docked stack.

When the docked stack is minimized its app windows are cropped
significantly so any screenshot taken will not display the apps
contain. So, we avoid taking a screenshot in that case.

This situation is going to be improve some in O when we switch
recents to also use saved surfaces in which cases it will be able
to display the last app content the user saw vs. just the app's
background color.

Bug: 29830173
Change-Id: I003aa074126ddcb57d5ff6dda756293146646196
---
 .../com/android/server/am/ActivityStack.java  | 42 ++++++++++++-------
 1 file changed, 27 insertions(+), 15 deletions(-)

diff --git a/services/core/java/com/android/server/am/ActivityStack.java b/services/core/java/com/android/server/am/ActivityStack.java
index 60d3d1ec349b1..1b552b5375e79 100644
--- a/services/core/java/com/android/server/am/ActivityStack.java
+++ b/services/core/java/com/android/server/am/ActivityStack.java
@@ -29,6 +29,7 @@ import static android.content.pm.ActivityInfo.CONFIG_SMALLEST_SCREEN_SIZE;
 import static android.content.pm.ActivityInfo.FLAG_RESUME_WHILE_PAUSING;
 import static android.content.pm.ActivityInfo.FLAG_SHOW_FOR_ALL_USERS;
 import static android.content.res.Configuration.SCREENLAYOUT_UNDEFINED;
+import static android.view.Display.DEFAULT_DISPLAY;
 import static com.android.server.am.ActivityManagerDebugConfig.DEBUG_ADD_REMOVE;
 import static com.android.server.am.ActivityManagerDebugConfig.DEBUG_ALL;
 import static com.android.server.am.ActivityManagerDebugConfig.DEBUG_APP;
@@ -68,6 +69,7 @@ import static com.android.server.am.ActivityManagerDebugConfig.POSTFIX_VISIBILIT
 import static com.android.server.am.ActivityManagerDebugConfig.TAG_AM;
 import static com.android.server.am.ActivityManagerDebugConfig.TAG_WITH_CLASS_NAME;
 import static com.android.server.am.ActivityManagerService.LOCK_SCREEN_SHOWN;
+import static com.android.server.am.ActivityManagerService.TAKE_FULLSCREEN_SCREENSHOTS;
 import static com.android.server.am.ActivityRecord.APPLICATION_ACTIVITY_TYPE;
 import static com.android.server.am.ActivityRecord.HOME_ACTIVITY_TYPE;
 import static com.android.server.am.ActivityRecord.STARTING_WINDOW_REMOVED;
@@ -669,7 +671,7 @@ final class ActivityStack {
 
     final boolean isOnHomeDisplay() {
         return isAttached() &&
-                mActivityContainer.mActivityDisplay.mDisplayId == Display.DEFAULT_DISPLAY;
+                mActivityContainer.mActivityDisplay.mDisplayId == DEFAULT_DISPLAY;
     }
 
     void moveToFront(String reason) {
@@ -1041,22 +1043,32 @@ final class ActivityStack {
 
         int w = mService.mThumbnailWidth;
         int h = mService.mThumbnailHeight;
-        float scale = 1f;
-        if (w > 0) {
-            if (DEBUG_SCREENSHOTS) Slog.d(TAG_SCREENSHOTS, "\tTaking screenshot");
 
-            // When this flag is set, we currently take the fullscreen screenshot of the activity
-            // but scaled to half the size.  This gives us a "good-enough" fullscreen thumbnail to
-            // use within SystemUI while keeping memory usage low.
-            if (ActivityManagerService.TAKE_FULLSCREEN_SCREENSHOTS) {
-                w = h = -1;
-                scale = mService.mFullscreenThumbnailScale;
-            }
-            return mWindowManager.screenshotApplications(who.appToken, Display.DEFAULT_DISPLAY,
-                    w, h, scale);
+        if (w <= 0) {
+            Slog.e(TAG, "\tInvalid thumbnail dimensions: " + w + "x" + h);
+            return null;
         }
-        Slog.e(TAG, "Invalid thumbnail dimensions: " + w + "x" + h);
-        return null;
+
+        if (mStackId == DOCKED_STACK_ID && mStackSupervisor.mIsDockMinimized) {
+            // When the docked stack is minimized its app windows are cropped significantly so any
+            // screenshot taken will not display the apps contain. So, we avoid taking a screenshot
+            // in that case.
+            if (DEBUG_SCREENSHOTS) Slog.e(TAG, "\tIn minimized docked stack");
+            return null;
+        }
+
+        float scale = 1f;
+        if (DEBUG_SCREENSHOTS) Slog.d(TAG_SCREENSHOTS, "\tTaking screenshot");
+
+        // When this flag is set, we currently take the fullscreen screenshot of the activity but
+        // scaled to half the size. This gives us a "good-enough" fullscreen thumbnail to use within
+        // SystemUI while keeping memory usage low.
+        if (TAKE_FULLSCREEN_SCREENSHOTS) {
+            w = h = -1;
+            scale = mService.mFullscreenThumbnailScale;
+        }
+
+        return mWindowManager.screenshotApplications(who.appToken, DEFAULT_DISPLAY, w, h, scale);
     }
 
     /**